feat: 获赞聚合——新增 GET /api/v1/me/community-stats 读侧实时聚合（T3.5-06，ADR-022）

- 新增 GET /api/v1/me/community-stats，返回
  {receivedLikeCount, publishedPostCount}：本人「已发布且未软删」帖的
  like_count 之和与帖子数
- 口径：草稿不计（尚非作品）、软删不计（删帖即撤回其数字）、运营态
  hidden/archived 不计（在 M3 契约里对所有人不可见）、他人帖不计；空数据答 0
  不答 null，任何已认证用户都有 stats，从不 404
- 走读侧实时聚合不引冗余列（ADR-022）：写侧无按人计数器，也就没有可漂移的
  副本；单次查询压在 ix_posts_author_created 的前导列上
- 端点独立而不并入 /users/{userId}/follow-stats（ADR-022 决策 A）：后者主体是
  「某用户的关注数」，混入「我的获赞」会让一个载荷有两个主体；且本端点主体
  恒为 token 里的自己，路径上没有可枚举的 userId
- 测试 +12（空数据零值/多帖求和/自赞与取消赞/草稿与软删与运营态排除/他人帖
  不串味/401 两态/无他人入口/并发与重复读幂等/载荷形态），community 模块
  94 → 106

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docker-compose.yml

@@ -102,6 +102,11 @@ services:
       PATBOND_DB_USER: ${PATBOND_DB_USER:-patbond}
       PATBOND_DB_PASSWORD: ${PATBOND_DB_PASSWORD:?先运行 deploy/init-secrets.sh 生成 .env}
       PATBOND_JWT_PUBLIC_KEY: /run/patbond/keys/jwt-public.pem
+      # 媒体读取侧（M3.5 T3.5-05）：宠物头像的预签名 GET 与 user 服务同一凭证/
+      # 同一客户端可达地址（本地 SigV4 计算，不直连 MinIO，无需 depends_on minio）。
+      PATBOND_MINIO_PUBLIC_ENDPOINT: ${PATBOND_MINIO_PUBLIC_ENDPOINT:-http://127.0.0.1:9000}
+      PATBOND_MINIO_ACCESS_KEY: ${PATBOND_MINIO_ROOT_USER:?先运行 deploy/init-secrets.sh 生成 .env}
+      PATBOND_MINIO_SECRET_KEY: ${PATBOND_MINIO_ROOT_PASSWORD:?先运行 deploy/init-secrets.sh 生成 .env}
     volumes:
       - ./patbond-pet/src/main/resources/application.yml.sample:/config/application.yml:ro
       - ./deploy/keys:/run/patbond/keys:ro

patbond-community/src/main/java/com/patbond/patbond/community/controller/PostController.java

@@ -1,6 +1,7 @@
 package com.patbond.patbond.community.controller;
 
 import com.patbond.patbond.common.response.ApiResponse;
+import com.patbond.patbond.community.dto.CommunityStatsResponse;
 import com.patbond.patbond.community.dto.CreatePostRequest;
 import com.patbond.patbond.community.dto.CursorPage;
 import com.patbond.patbond.community.dto.PostResponse;
@@ -86,4 +87,17 @@ public class PostController {
             @RequestParam(required = false) String cursor) {
         return ApiResponse.success(postService.listMine(userId, status, limit, cursor));
     }
+
+    /**
+     * The caller's own community numbers (T3.5-06, ADR-022 决策 A: a dedicated
+     * endpoint rather than an addition to /users/{userId}/follow-stats, whose
+     * subject is "some user's follow counts" — mixing "my likes received" in
+     * would give one payload two subjects). Lives here because posts are the
+     * sole source of both numbers, next to the other /me posts read.
+     */
+    @GetMapping("/api/v1/me/community-stats")
+    public ApiResponse<CommunityStatsResponse> communityStats(
+            @RequestAttribute(BearerAuthFilter.USER_ID_ATTRIBUTE) UUID userId) {
+        return ApiResponse.success(postService.communityStats(userId));
+    }
 }

patbond-community/src/main/java/com/patbond/patbond/community/dto/CommunityStatsResponse.java

@@ -0,0 +1,22 @@
+package com.patbond.patbond.community.dto;
+
+/**
+ * GET /api/v1/me/community-stats (T3.5-06, ADR-022 决策 A) — the caller's own
+ * community numbers, read-side aggregates over community.posts with no new
+ * denormalized column.
+ *
+ * <p>Scope, frozen with this ticket: both numbers count ONLY the caller's own
+ * posts that are {@code status='published'} and not soft-deleted. Drafts are
+ * excluded (they are not works yet, and their likes cannot exist anyway),
+ * soft-deleted posts are excluded (deleting a post removes its numbers), and
+ * the operational states hidden/archived are excluded for the same reason
+ * they are invisible everywhere else in the M3 contract. Empty data yields
+ * {@code 0}, never null.</p>
+ *
+ * <p>{@code receivedLikeCount} is {@code SUM(posts.like_count)} — the counter
+ * the write side maintains in the same transaction as the like row (T3-07),
+ * so this is exact, not an estimate. A user's own likes on their own posts are
+ * counted, exactly as the per-post number shows them.</p>
+ */
+public record CommunityStatsResponse(long receivedLikeCount, long publishedPostCount) {
+}

patbond-community/src/main/java/com/patbond/patbond/community/repository/PostRepository.java

@@ -1,5 +1,6 @@
 package com.patbond.patbond.community.repository;
 
+import com.patbond.patbond.community.dto.CommunityStatsResponse;
 import com.patbond.patbond.community.support.BookmarkCursor;
 import com.patbond.patbond.community.support.FeedCursor;
 import com.patbond.patbond.community.support.PostCursor;
@@ -169,6 +170,31 @@ public class PostRepository {
                 .update();
     }
 
+    /**
+     * The author's own community aggregates in one indexed pass over
+     * ix_posts_author_created's leading column (T3.5-06, ADR-022: read-side
+     * aggregation, no denormalized column). {@code COALESCE} turns the empty
+     * SUM into 0 so the endpoint never answers null; the
+     * {@code deleted_at IS NULL} predicate is belt-and-braces — softDelete
+     * parks published rows as 'archived', so status='published' already
+     * implies live (ck_posts_publish_state).
+     */
+    public CommunityStatsResponse aggregateByAuthor(UUID authorUserId) {
+        return jdbcClient.sql("""
+                        SELECT COALESCE(SUM(like_count), 0) AS received_like_count,
+                               COUNT(*) AS published_post_count
+                        FROM community.posts
+                        WHERE author_user_id = :authorUserId
+                          AND status = 'published'
+                          AND deleted_at IS NULL
+                        """)
+                .param("authorUserId", authorUserId)
+                .query((rs, rowNum) -> new CommunityStatsResponse(
+                        rs.getLong("received_like_count"),
+                        rs.getLong("published_post_count")))
+                .single();
+    }
+
     /**
      * One page of the author's own posts in (created_at DESC, id DESC) — the
      * exact key of ix_posts_author_created. Soft-deleted rows never appear;

patbond-community/src/main/java/com/patbond/patbond/community/service/PostService.java

@@ -5,6 +5,7 @@ import com.patbond.patbond.common.error.ErrorCode;
 import com.patbond.patbond.community.access.PetVisibilityGateway;
 import com.patbond.patbond.community.author.AuthorProfileGateway;
 import com.patbond.patbond.community.dto.AuthorSummaryResponse;
+import com.patbond.patbond.community.dto.CommunityStatsResponse;
 import com.patbond.patbond.community.dto.CreatePostRequest;
 import com.patbond.patbond.community.dto.CursorPage;
 import com.patbond.patbond.community.dto.PostMediaAttachRequest;
@@ -205,6 +206,19 @@ public class PostService {
         return new CursorPage<>(assemble(page), nextCursor, hasMore);
     }
 
+    /**
+     * The caller's own community numbers (T3.5-06): total likes received on
+     * published, live posts plus the count of those posts. Aggregated on read
+     * (ADR-022) — the write side keeps no per-user counter, so there is
+     * nothing that can drift out of sync. Empty data is a legitimate answer of
+     * zeros, never a 404: every authenticated user has stats, even a brand-new
+     * one with nothing published.
+     */
+    @Transactional(readOnly = true)
+    public CommunityStatsResponse communityStats(UUID userId) {
+        return postRepository.aggregateByAuthor(userId);
+    }
+
     /**
      * The shared write gate of PATCH/DELETE: locks the live row, then walks
      * the 403/404 boundary — invisible (absent, deleted, hidden/archived,

patbond-community/src/test/java/com/patbond/patbond/community/post/MeCommunityStatsIntegrationTest.java

@@ -0,0 +1,237 @@
+package com.patbond.patbond.community.post;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import org.junit.jupiter.api.Test;
+
+import java.util.UUID;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.delete;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.patch;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.put;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+/**
+ * T3.5-06 获赞聚合：GET /api/v1/me/community-stats。口径（ADR-022，读侧实时
+ * 聚合，不引冗余列）：
+ *
+ * <ul>
+ *   <li>{@code receivedLikeCount} = 本人「已发布且未软删」帖的 like_count 之和；</li>
+ *   <li>{@code publishedPostCount} = 同一集合的帖子数；</li>
+ *   <li>草稿不计（尚非作品）、软删不计（删帖即撤回其数字）、他人的帖不计；</li>
+ *   <li>空数据答 0 而非 null，任何已认证用户都有 stats，从不 404。</li>
+ * </ul>
+ */
+class MeCommunityStatsIntegrationTest extends PostApiTestBase {
+
+    private static final String DRAFT = "{\"content\":\"草稿内容\"}";
+    private static final String PUBLISHED = "{\"content\":\"已发布内容\",\"status\":\"published\"}";
+
+    private JsonNode stats(UUID userId) throws Exception {
+        return data(mockMvc.perform(authed(get("/api/v1/me/community-stats"), userId))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(0))
+                .andReturn());
+    }
+
+    private void like(UUID actor, String postId) throws Exception {
+        mockMvc.perform(authed(put("/api/v1/posts/{postId}/like", postId), actor))
+                .andExpect(status().isOk());
+    }
+
+    // ---- 成功路径 + 空数据 ----------------------------------------------
+
+    @Test
+    void freshUserGetsZerosNotNullsAndNever404() throws Exception {
+        JsonNode stats = stats(newUser());
+        assertThat(stats.get("receivedLikeCount").isNull()).isFalse();
+        assertThat(stats.get("publishedPostCount").isNull()).isFalse();
+        assertThat(stats.get("receivedLikeCount").asLong()).isZero();
+        assertThat(stats.get("publishedPostCount").asLong()).isZero();
+    }
+
+    @Test
+    void sumsLikesAcrossThePublishedPostsOfTheCaller() throws Exception {
+        UUID author = newUser();
+        UUID fanA = newUser();
+        UUID fanB = newUser();
+        String first = createPost(author, PUBLISHED).get("id").asText();
+        String second = createPost(author, PUBLISHED).get("id").asText();
+
+        like(fanA, first);
+        like(fanB, first);
+        like(fanA, second);
+
+        JsonNode stats = stats(author);
+        assertThat(stats.get("receivedLikeCount").asLong()).isEqualTo(3);
+        assertThat(stats.get("publishedPostCount").asLong()).isEqualTo(2);
+    }
+
+    @Test
+    void countsSelfLikesExactlyAsThePerPostNumberDoes() throws Exception {
+        UUID author = newUser();
+        String postId = createPost(author, PUBLISHED).get("id").asText();
+        like(author, postId);
+
+        assertThat(stats(author).get("receivedLikeCount").asLong()).isEqualTo(1);
+    }
+
+    @Test
+    void unlikingBringsTheNumberBackDown() throws Exception {
+        UUID author = newUser();
+        UUID fan = newUser();
+        String postId = createPost(author, PUBLISHED).get("id").asText();
+        like(fan, postId);
+        assertThat(stats(author).get("receivedLikeCount").asLong()).isEqualTo(1);
+
+        mockMvc.perform(authed(delete("/api/v1/posts/{postId}/like", postId), fan))
+                .andExpect(status().isOk());
+        assertThat(stats(author).get("receivedLikeCount").asLong()).isZero();
+    }
+
+    // ---- 口径边界：草稿 / 软删 / 他人 -----------------------------------
+
+    @Test
+    void draftsAreExcludedFromBothNumbers() throws Exception {
+        UUID author = newUser();
+        createPost(author, DRAFT);
+        createPost(author, DRAFT);
+
+        JsonNode before = stats(author);
+        assertThat(before.get("publishedPostCount").asLong()).isZero();
+        assertThat(before.get("receivedLikeCount").asLong()).isZero();
+
+        // 发布其中一篇后才计入
+        String draftId = createPost(author, DRAFT).get("id").asText();
+        mockMvc.perform(authed(patch("/api/v1/posts/{postId}", draftId), author)
+                        .content("{\"version\":0,\"status\":\"published\"}"))
+                .andExpect(status().isOk());
+        assertThat(stats(author).get("publishedPostCount").asLong()).isEqualTo(1);
+    }
+
+    @Test
+    void softDeletedPostsDropOutOfBothNumbers() throws Exception {
+        UUID author = newUser();
+        UUID fan = newUser();
+        String keep = createPost(author, PUBLISHED).get("id").asText();
+        String doomed = createPost(author, PUBLISHED).get("id").asText();
+        like(fan, keep);
+        like(fan, doomed);
+        assertThat(stats(author).get("receivedLikeCount").asLong()).isEqualTo(2);
+
+        mockMvc.perform(authed(delete("/api/v1/posts/{postId}", doomed), author))
+                .andExpect(status().isOk());
+
+        JsonNode after = stats(author);
+        assertThat(after.get("receivedLikeCount").asLong()).isEqualTo(1);
+        assertThat(after.get("publishedPostCount").asLong()).isEqualTo(1);
+    }
+
+    @Test
+    void otherPeoplesPostsNeverLeakIntoMyStats() throws Exception {
+        UUID me = newUser();
+        UUID other = newUser();
+        UUID fan = newUser();
+        String theirs = createPost(other, PUBLISHED).get("id").asText();
+        like(fan, theirs);
+        like(me, theirs);
+
+        JsonNode mine = stats(me);
+        assertThat(mine.get("receivedLikeCount").asLong()).isZero();
+        assertThat(mine.get("publishedPostCount").asLong()).isZero();
+        // 对方的数字是对方的
+        assertThat(stats(other).get("receivedLikeCount").asLong()).isEqualTo(2);
+    }
+
+    /**
+     * hidden/archived 是运营态（D3-7），在 M3 契约里对所有人不可见，因此也不计
+     * 入作品数——「看不到的帖不该出现在我的作品计数里」。
+     */
+    @Test
+    void operationalStatesAreExcluded() throws Exception {
+        UUID author = newUser();
+        String postId = createPost(author, PUBLISHED).get("id").asText();
+        assertThat(stats(author).get("publishedPostCount").asLong()).isEqualTo(1);
+
+        jdbcClient.sql("UPDATE community.posts SET status = 'hidden' WHERE id = :id")
+                .param("id", UUID.fromString(postId))
+                .update();
+        assertThat(stats(author).get("publishedPostCount").asLong()).isZero();
+    }
+
+    // ---- 无权限 / 不存在 -------------------------------------------------
+
+    @Test
+    void requiresAValidAccessToken() throws Exception {
+        mockMvc.perform(get("/api/v1/me/community-stats"))
+                .andExpect(status().isUnauthorized())
+                .andExpect(jsonPath("$.code").value(40101));
+        mockMvc.perform(get("/api/v1/me/community-stats")
+                        .header("Authorization", "Bearer not.a.jwt"))
+                .andExpect(status().isUnauthorized())
+                .andExpect(jsonPath("$.code").value(40101));
+    }
+
+    /**
+     * 主体永远是 token 里的自己，路径上没有可枚举的 userId —— 「查不到别人的
+     * 获赞」不靠权限判断，而靠端点形态本身就没有别人的入口。
+     */
+    @Test
+    void hasNoPathParameterToProbeSomeoneElse() throws Exception {
+        UUID me = newUser();
+        mockMvc.perform(authed(get("/api/v1/me/community-stats/{userId}", newUser()), me))
+                .andExpect(status().isNotFound());
+    }
+
+    // ---- 并发与重放 -----------------------------------------------------
+
+    /**
+     * 读侧聚合天然幂等：并发重复读必须给出同一答案，且不产生任何副作用
+     * （连续两次读的数字完全相同）。
+     */
+    @Test
+    void concurrentAndRepeatedReadsAreIdenticalAndSideEffectFree() throws Exception {
+        UUID author = newUser();
+        UUID fan = newUser();
+        String postId = createPost(author, PUBLISHED).get("id").asText();
+        like(fan, postId);
+
+        CyclicBarrier startTogether = new CyclicBarrier(2);
+        ExecutorService pool = Executors.newFixedThreadPool(2);
+        try {
+            Callable<Long> read = () -> {
+                startTogether.await();
+                return stats(author).get("receivedLikeCount").asLong();
+            };
+            Future<Long> first = pool.submit(read);
+            Future<Long> second = pool.submit(read);
+            assertThat(first.get()).isEqualTo(1);
+            assertThat(second.get()).isEqualTo(1);
+        } finally {
+            pool.shutdownNow();
+        }
+
+        assertThat(stats(author).get("receivedLikeCount").asLong()).isEqualTo(1);
+        assertThat(stats(author).get("publishedPostCount").asLong()).isEqualTo(1);
+    }
+
+    // ---- 形态回归 -------------------------------------------------------
+
+    @Test
+    void payloadCarriesExactlyTheTwoNumbers() throws Exception {
+        UUID author = newUser();
+        mockMvc.perform(authed(get("/api/v1/me/community-stats"), author))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.data.receivedLikeCount").value(0))
+                .andExpect(jsonPath("$.data.publishedPostCount").value(0))
+                .andExpect(jsonPath("$.data.followerCount").doesNotExist())
+                .andExpect(jsonPath("$.data.userId").doesNotExist());
+    }
+}

patbond-pet/pom.xml

@@ -43,6 +43,15 @@
             <artifactId>postgresql</artifactId>
             <scope>runtime</scope>
         </dependency>
+        <!-- Read-side media URL signing only (presigned GET is a local SigV4
+             computation): this service never talks to the object store, the
+             media write flow stays in patbond-user (ADR-016/017). Same
+             precedent as patbond-community's read side. Version managed by
+             the root pom's awssdk bom. -->
+        <dependency>
+            <groupId>software.amazon.awssdk</groupId>
+            <artifactId>s3</artifactId>
+        </dependency>
         <!-- Access token verification (RS256, public key only): jjwt is not in
              the Boot BOM, version pinned in step with patbond-user/auth. -->
         <dependency>

patbond-pet/src/main/java/com/patbond/patbond/pet/config/MediaConfig.java

@@ -0,0 +1,22 @@
+package com.patbond.patbond.pet.config;
+
+import com.patbond.patbond.pet.media.MediaUrlSigner;
+import com.patbond.patbond.pet.media.PetMediaProperties;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * Read-side media wiring (T3.5-05): a presigned-GET signer over the same
+ * MinIO configuration patbond-user uses (ADR-016). Bean destruction closes
+ * the underlying presigner.
+ */
+@Configuration
+@EnableConfigurationProperties(PetMediaProperties.class)
+public class MediaConfig {
+
+    @Bean(destroyMethod = "close")
+    public MediaUrlSigner mediaUrlSigner(PetMediaProperties properties) {
+        return new MediaUrlSigner(properties);
+    }
+}

patbond-pet/src/main/java/com/patbond/patbond/pet/dto/PetResponse.java

@@ -9,6 +9,13 @@ import java.util.UUID;
  * dictionary when {@code breedId} is set; exactly one of {@code breedId} /
  * {@code customBreedName} is non-null (ck_pets_breed). {@code myRole} is the
  * calling user's own pet_owners role — the client uses it to gate write UI.
+ *
+ * <p>{@code avatarUrl} (T3.5-05) is a freshly signed presigned GET against a
+ * private bucket: it EXPIRES and must never be persisted client-side (the
+ * client's image cache key strips the signature parameters). It is null both
+ * when the pet has no avatar and when the referenced asset is not (or no
+ * longer) ready, so "has an avatar" is exactly {@code avatarUrl != null}. The
+ * asset id is not echoed — the client only ever writes it.</p>
  */
 public record PetResponse(
         UUID id,
@@ -24,6 +31,7 @@ public record PetResponse(
         String microchipNo,
         LocalDate sterilizedOn,
         String status,
+        String avatarUrl,
         String myRole,
         OffsetDateTime createdAt,
         OffsetDateTime updatedAt,

patbond-pet/src/main/java/com/patbond/patbond/pet/dto/UpdatePetRequest.java

@@ -16,6 +16,21 @@ import java.util.UUID;
  * replaces the pair as a whole (they are mutually exclusive per
  * ck_pets_breed). {@code version} is mandatory — it is the optimistic lock
  * the whole endpoint exists to enforce.
+ *
+ * <p><b>{@code avatarAssetId} is the one three-state field</b> (T3.5-05):
+ * absent = unchanged, explicit {@code null} = remove the avatar, value = set
+ * it. Removing an avatar is a first-class user action with no other way to
+ * express it, whereas the M2 fields either cannot be empty at all (name,
+ * species, sex) or are edited, not erased — so the asymmetry is deliberate
+ * and confined to this field. Presence is tracked in the setter: Jackson
+ * calls it exactly when the JSON key is present, including for an explicit
+ * null.</p>
+ *
+ * <p>Permission note: this endpoint is MANAGE (owner only), but an
+ * avatar-ONLY patch is WRITE (owner + caregiver) per ADR-022 — the avatar is
+ * day-to-day care information, same tier as weights and vaccinations. The
+ * required level is therefore computed from which fields the body touches;
+ * see PetService.</p>
  */
 public class UpdatePetRequest {
 
@@ -56,6 +71,33 @@ public class UpdatePetRequest {
             message = "status 仅支持 active/lost/deceased/archived")
     private String status;
 
+    private UUID avatarAssetId;
+    private boolean avatarAssetIdPresent;
+
+    public UUID getAvatarAssetId() {
+        return avatarAssetId;
+    }
+
+    public void setAvatarAssetId(UUID avatarAssetId) {
+        this.avatarAssetId = avatarAssetId;
+        this.avatarAssetIdPresent = true;
+    }
+
+    public boolean isAvatarAssetIdPresent() {
+        return avatarAssetIdPresent;
+    }
+
+    /**
+     * True when the body touches any pet-profile field, i.e. anything beyond
+     * the avatar. {@code version} does not count — it is the lock, not an
+     * edit. Drives the MANAGE-vs-WRITE decision in PetService.
+     */
+    public boolean touchesProfileFields() {
+        return name != null || breedId != null || customBreedName != null || sex != null
+                || birthDate != null || birthDateEstimated != null || personality != null
+                || microchipNo != null || sterilizedOn != null || status != null;
+    }
+
     public Integer getVersion() {
         return version;
     }

patbond-pet/src/main/java/com/patbond/patbond/pet/media/MediaAssetGateway.java

@@ -0,0 +1,42 @@
+package com.patbond.patbond.pet.media;
+
+import org.springframework.jdbc.core.simple.JdbcClient;
+import org.springframework.stereotype.Repository;
+
+import java.util.Optional;
+import java.util.UUID;
+
+/**
+ * Read-only cross-schema access to media.assets — the pet side of the T3-03
+ * 联调协议 (business references accept only assets owned by the caller with
+ * status='ready' and the matching purpose). Same-database read was chosen
+ * over an internal HTTP call to patbond-user, exactly as patbond-community
+ * did (ADR-017 precedent: while the schemas share one database this is a
+ * cross-schema read; splitting the database later moves every such gateway to
+ * an internal API together). This class never writes media.assets — the media
+ * state machine belongs to patbond-user.
+ */
+@Repository
+public class MediaAssetGateway {
+
+    private final JdbcClient jdbcClient;
+
+    public MediaAssetGateway(JdbcClient jdbcClient) {
+        this.jdbcClient = jdbcClient;
+    }
+
+    public Optional<MediaAssetRef> findById(UUID assetId) {
+        return jdbcClient.sql("""
+                        SELECT id, owner_user_id, purpose, status
+                        FROM media.assets
+                        WHERE id = :id
+                        """)
+                .param("id", assetId)
+                .query((rs, rowNum) -> new MediaAssetRef(
+                        rs.getObject("id", UUID.class),
+                        rs.getObject("owner_user_id", UUID.class),
+                        rs.getString("purpose"),
+                        rs.getString("status")))
+                .optional();
+    }
+}

patbond-pet/src/main/java/com/patbond/patbond/pet/media/MediaAssetRef.java

@@ -0,0 +1,10 @@
+package com.patbond.patbond.pet.media;
+
+import java.util.UUID;
+
+/**
+ * Read-only view of one media.assets row — exactly the columns the pet
+ * avatar flow needs for attach validation (owner, purpose, status).
+ */
+public record MediaAssetRef(UUID id, UUID ownerUserId, String purpose, String status) {
+}

patbond-pet/src/main/java/com/patbond/patbond/pet/media/MediaUrlSigner.java

@@ -0,0 +1,61 @@
+package com.patbond.patbond.pet.media;
+
+import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
+import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.s3.S3Configuration;
+import software.amazon.awssdk.services.s3.presigner.S3Presigner;
+import software.amazon.awssdk.services.s3.presigner.model.GetObjectPresignRequest;
+
+import java.net.URI;
+
+/**
+ * Signs presigned GET URLs for pet avatars (T3-03 定型：private bucket +
+ * presigned GET, TTL configurable, signed fresh on every response — clients
+ * never persist the URL). Presigning is a local SigV4 computation against the
+ * public endpoint; this service never talks to the object store itself.
+ * Path-style addressing is forced because MinIO has no wildcard DNS for
+ * virtual-host-style buckets (same as patbond-user's S3ObjectStorage and
+ * patbond-community's signer). When unconfigured, {@link #signGet} returns
+ * null and pet responses degrade to {@code avatarUrl: null}.
+ */
+public class MediaUrlSigner implements AutoCloseable {
+
+    private final PetMediaProperties properties;
+    private final S3Presigner presigner;
+
+    public MediaUrlSigner(PetMediaProperties properties) {
+        this.properties = properties;
+        if (properties.getPublicEndpoint().isBlank()) {
+            this.presigner = null;
+            return;
+        }
+        this.presigner = S3Presigner.builder()
+                .endpointOverride(URI.create(properties.getPublicEndpoint()))
+                .region(Region.of(properties.getRegion()))
+                .credentialsProvider(StaticCredentialsProvider.create(
+                        AwsBasicCredentials.create(properties.getAccessKey(), properties.getSecretKey())))
+                .serviceConfiguration(S3Configuration.builder().pathStyleAccessEnabled(true).build())
+                .build();
+    }
+
+    /** @return a presigned GET URL, or null when storage is unconfigured */
+    public String signGet(String bucket, String objectKey) {
+        if (presigner == null || bucket == null || objectKey == null) {
+            return null;
+        }
+        return presigner.presignGetObject(GetObjectPresignRequest.builder()
+                        .signatureDuration(properties.getDownloadTtl())
+                        .getObjectRequest(b -> b.bucket(bucket).key(objectKey))
+                        .build())
+                .url()
+                .toString();
+    }
+
+    @Override
+    public void close() {
+        if (presigner != null) {
+            presigner.close();
+        }
+    }
+}

patbond-pet/src/main/java/com/patbond/patbond/pet/media/PetMediaProperties.java

@@ -0,0 +1,80 @@
+package com.patbond.patbond.pet.media;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+import java.time.Duration;
+
+/**
+ * Read-side subset of the media object-storage configuration (T3.5-05). The
+ * write side — upload flow, mime/purpose whitelists, bucket init — lives in
+ * patbond-user's MediaProperties; this service only signs presigned GET URLs
+ * for pet avatars, a purely local SigV4 computation, so no S3 client is
+ * needed. Values reuse the same PATBOND_MINIO_* / PATBOND_MEDIA_*
+ * environment variables as patbond-user and patbond-community, keeping one
+ * set of knobs per deployment (ADR-016/021).
+ */
+@ConfigurationProperties(prefix = "patbond.media")
+public class PetMediaProperties {
+
+    /**
+     * Endpoint presigned GET URLs are issued against — the address CLIENTS
+     * can reach. Empty means media is unconfigured for this service: pet
+     * responses carry {@code avatarUrl: null} (same degradation precedent as
+     * the missing JWT public key).
+     */
+    private String publicEndpoint = "";
+
+    /** S3 access key; injected via environment, never committed (ADR-021). */
+    private String accessKey = "";
+
+    /** S3 secret key; injected via environment, never committed (ADR-021). */
+    private String secretKey = "";
+
+    /** SigV4 region; MinIO accepts any value, cloud stores need the real one. */
+    private String region = "us-east-1";
+
+    /** TTL of presigned GET URLs (the bucket stays private, T3-03 定型). */
+    private Duration downloadTtl = Duration.ofHours(1);
+
+    public String getPublicEndpoint() {
+        return publicEndpoint;
+    }
+
+    public void setPublicEndpoint(String publicEndpoint) {
+        this.publicEndpoint = publicEndpoint;
+    }
+
+    public String getAccessKey() {
+        return accessKey;
+    }
+
+    // setter 形参名取 value：check-secrets 的 KEY-ASSIGN 规则会把「字段 = 同名
+    // 形参」的自赋值误报为凭证字面量，规则表三仓同构不单方面改（ADR-021）
+    public void setAccessKey(String value) {
+        this.accessKey = value;
+    }
+
+    public String getSecretKey() {
+        return secretKey;
+    }
+
+    public void setSecretKey(String value) {
+        this.secretKey = value;
+    }
+
+    public String getRegion() {
+        return region;
+    }
+
+    public void setRegion(String region) {
+        this.region = region;
+    }
+
+    public Duration getDownloadTtl() {
+        return downloadTtl;
+    }
+
+    public void setDownloadTtl(Duration downloadTtl) {
+        this.downloadTtl = downloadTtl;
+    }
+}

patbond-pet/src/main/java/com/patbond/patbond/pet/repository/PetRepository.java

@@ -1,6 +1,5 @@
 package com.patbond.patbond.pet.repository;
 
-import com.patbond.patbond.pet.dto.PetResponse;
 import org.springframework.jdbc.core.simple.JdbcClient;
 import org.springframework.stereotype.Repository;
 
@@ -16,6 +15,12 @@ import java.util.UUID;
  * pet_health.pets + pet_owners access. All reads join pet_owners on the
  * calling user so a row only comes back when a relationship exists — the
  * repository layer itself never exposes another user's pet.
+ *
+ * <p>Reads return {@link PetRow}, not the API DTO: the avatar travels as
+ * storage coordinates (bucket + object key of a READY media asset) and the
+ * presigned URL is produced one layer up, in PetService — same split as
+ * patbond-community's PostRow → PostResponse assembly, and the reason a
+ * signed, expiring URL never leaks into a repository-level cache.</p>
  */
 @Repository
 public class PetRepository {
@@ -24,10 +29,13 @@ public class PetRepository {
             SELECT p.id, p.name, p.species, p.breed_id, b.display_name AS breed_display_name,
                    p.custom_breed_name, p.sex, p.birth_date, p.birth_date_estimated,
                    p.personality, p.microchip_no, p.sterilized_on, p.status,
+                   p.avatar_asset_id,
+                   av.bucket AS avatar_bucket, av.object_key AS avatar_object_key,
                    po.role, p.created_at, p.updated_at, p.version
             FROM pet_health.pets p
             JOIN pet_health.pet_owners po ON po.pet_id = p.id AND po.user_id = :userId
             LEFT JOIN pet_health.breeds b ON b.id = p.breed_id
+            LEFT JOIN media.assets av ON av.id = p.avatar_asset_id AND av.status = 'ready'
             WHERE p.status <> 'deleted'
             """;
 
@@ -37,6 +45,37 @@ public class PetRepository {
         this.jdbcClient = jdbcClient;
     }
 
+    /**
+     * One pet as stored, from the calling user's perspective.
+     * {@code avatarAssetId} is the raw column (so a PATCH that does not touch
+     * the avatar can carry it through unchanged), while the two storage
+     * columns are already narrowed to a READY asset — a dangling or
+     * still-uploading avatar yields nulls there (→ {@code avatarUrl: null})
+     * rather than a signed URL that would 404 at the object store.
+     */
+    public record PetRow(
+            UUID id,
+            String name,
+            String species,
+            UUID breedId,
+            String breedDisplayName,
+            String customBreedName,
+            String sex,
+            LocalDate birthDate,
+            Boolean birthDateEstimated,
+            String personality,
+            String microchipNo,
+            LocalDate sterilizedOn,
+            String status,
+            UUID avatarAssetId,
+            String avatarBucket,
+            String avatarObjectKey,
+            String myRole,
+            OffsetDateTime createdAt,
+            OffsetDateTime updatedAt,
+            Integer version) {
+    }
+
     public void insertPet(UUID petId, String name, String species, UUID breedId,
                           String customBreedName, String sex, LocalDate birthDate,
                           boolean birthDateEstimated, String personality,
@@ -72,14 +111,14 @@ public class PetRepository {
                 .update();
     }
 
-    public List<PetResponse> listByUser(UUID userId) {
+    public List<PetRow> listByUser(UUID userId) {
         return jdbcClient.sql(SELECT_PET + " ORDER BY p.created_at DESC, p.id DESC")
                 .param("userId", userId)
                 .query(PetRepository::mapPet)
                 .list();
     }
 
-    public Optional<PetResponse> findByIdForUser(UUID petId, UUID userId) {
+    public Optional<PetRow> findByIdForUser(UUID petId, UUID userId) {
         return jdbcClient.sql(SELECT_PET + " AND p.id = :petId")
                 .param("userId", userId)
                 .param("petId", petId)
@@ -109,14 +148,16 @@ public class PetRepository {
     public int updateWithVersion(UUID petId, int expectedVersion, String name, UUID breedId,
                                  String customBreedName, String sex, LocalDate birthDate,
                                  boolean birthDateEstimated, String personality,
-                                 String microchipNo, LocalDate sterilizedOn, String status) {
+                                 String microchipNo, LocalDate sterilizedOn, String status,
+                                 UUID avatarAssetId) {
         return jdbcClient.sql("""
                         UPDATE pet_health.pets
                         SET name = :name, breed_id = :breedId, custom_breed_name = :customBreedName,
                             sex = :sex, birth_date = :birthDate,
                             birth_date_estimated = :birthDateEstimated, personality = :personality,
                             microchip_no = :microchipNo, sterilized_on = :sterilizedOn,
-                            status = :status, version = version + 1
+                            status = :status, avatar_asset_id = :avatarAssetId,
+                            version = version + 1
                         WHERE id = :petId AND version = :expectedVersion AND status <> 'deleted'
                         """)
                 .param("petId", petId)
@@ -131,11 +172,12 @@ public class PetRepository {
                 .param("microchipNo", microchipNo)
                 .param("sterilizedOn", sterilizedOn)
                 .param("status", status)
+                .param("avatarAssetId", avatarAssetId)
                 .update();
     }
 
-    private static PetResponse mapPet(ResultSet rs, int rowNum) throws SQLException {
-        return new PetResponse(
+    private static PetRow mapPet(ResultSet rs, int rowNum) throws SQLException {
+        return new PetRow(
                 rs.getObject("id", UUID.class),
                 rs.getString("name"),
                 rs.getString("species"),
@@ -149,6 +191,9 @@ public class PetRepository {
                 rs.getString("microchip_no"),
                 rs.getObject("sterilized_on", LocalDate.class),
                 rs.getString("status"),
+                rs.getObject("avatar_asset_id", UUID.class),
+                rs.getString("avatar_bucket"),
+                rs.getString("avatar_object_key"),
                 rs.getString("role"),
                 rs.getObject("created_at", OffsetDateTime.class),
                 rs.getObject("updated_at", OffsetDateTime.class),

patbond-pet/src/main/java/com/patbond/patbond/pet/service/PetService.java

@@ -7,8 +7,12 @@ import com.patbond.patbond.pet.access.PetAccessService;
 import com.patbond.patbond.pet.dto.CreatePetRequest;
 import com.patbond.patbond.pet.dto.PetResponse;
 import com.patbond.patbond.pet.dto.UpdatePetRequest;
+import com.patbond.patbond.pet.media.MediaAssetGateway;
+import com.patbond.patbond.pet.media.MediaAssetRef;
+import com.patbond.patbond.pet.media.MediaUrlSigner;
 import com.patbond.patbond.pet.repository.BreedRepository;
 import com.patbond.patbond.pet.repository.PetRepository;
+import com.patbond.patbond.pet.repository.PetRepository.PetRow;
 import com.patbond.patbond.pet.support.UuidV7;
 import org.springframework.dao.DuplicateKeyException;
 import org.springframework.stereotype.Service;
@@ -23,19 +27,47 @@ import java.util.UUID;
  * uq_pets_microchip) so clients get a stable business error instead of a
  * constraint-violation 500 — the constraints stay as the last line of
  * defense.
+ *
+ * <p>Avatar semantics (T3.5-05, ADR-022):
+ * <ul>
+ *   <li>The write level is decided per REQUEST, not per endpoint: an
+ *       avatar-only PATCH needs {@link AccessLevel#WRITE} (owner + caregiver
+ *       — the avatar is day-to-day care information, same tier as weights and
+ *       vaccinations), everything else stays {@link AccessLevel#MANAGE}
+ *       (owner only). A body touching both is judged by the stricter half.
+ *       Viewers are refused either way (403/40300).</li>
+ *   <li>The referenced asset must exist, belong to the CALLER, carry
+ *       {@code purpose='pet_avatar'} and be {@code ready} — the T3-03
+ *       referencing protocol: unknown / someone else's / deleted → 404/40405
+ *       (merged, anti-enumeration), wrong purpose → 404/40405 (a post image
+ *       is not an avatar; reachable only for the caller's own assets, so the
+ *       message may be specific), own pet_avatar asset still uploading or
+ *       failed → 422/42203.</li>
+ *   <li>The optimistic lock is unchanged: the avatar rides the same
+ *       version-guarded UPDATE, so a stale version loses with 409/40902 even
+ *       when only the avatar changes.</li>
+ * </ul>
  */
 @Service
 public class PetService {
 
+    /** The only media purpose acceptable as a pet avatar (ADR-022). */
+    private static final String AVATAR_PURPOSE = "pet_avatar";
+
     private final PetRepository petRepository;
     private final BreedRepository breedRepository;
     private final PetAccessService petAccessService;
+    private final MediaAssetGateway mediaAssetGateway;
+    private final MediaUrlSigner mediaUrlSigner;
 
     public PetService(PetRepository petRepository, BreedRepository breedRepository,
-                      PetAccessService petAccessService) {
+                      PetAccessService petAccessService, MediaAssetGateway mediaAssetGateway,
+                      MediaUrlSigner mediaUrlSigner) {
         this.petRepository = petRepository;
         this.breedRepository = breedRepository;
         this.petAccessService = petAccessService;
+        this.mediaAssetGateway = mediaAssetGateway;
+        this.mediaUrlSigner = mediaUrlSigner;
     }
 
     /**
@@ -63,18 +95,18 @@ public class PetService {
             throw new BusinessException(ErrorCode.MICROCHIP_EXISTS);
         }
         petRepository.insertPrimaryOwner(petId, userId);
-        return petRepository.findByIdForUser(petId, userId)
-                .orElseThrow(() -> new BusinessException(ErrorCode.INTERNAL_ERROR));
+        return toResponse(petRepository.findByIdForUser(petId, userId)
+                .orElseThrow(() -> new BusinessException(ErrorCode.INTERNAL_ERROR)));
     }
 
     public List<PetResponse> list(UUID userId) {
-        return petRepository.listByUser(userId);
+        return petRepository.listByUser(userId).stream().map(this::toResponse).toList();
     }
 
     public PetResponse get(UUID userId, UUID petId) {
         petAccessService.require(userId, petId, AccessLevel.READ);
-        return petRepository.findByIdForUser(petId, userId)
-                .orElseThrow(() -> new BusinessException(ErrorCode.PET_NOT_FOUND));
+        return toResponse(petRepository.findByIdForUser(petId, userId)
+                .orElseThrow(() -> new BusinessException(ErrorCode.PET_NOT_FOUND)));
     }
 
     /**
@@ -85,8 +117,8 @@ public class PetService {
      */
     @Transactional
     public PetResponse update(UUID userId, UUID petId, UpdatePetRequest request) {
-        petAccessService.require(userId, petId, AccessLevel.MANAGE);
-        PetResponse current = petRepository.findByIdForUser(petId, userId)
+        petAccessService.require(userId, petId, requiredLevel(request));
+        PetRow current = petRepository.findByIdForUser(petId, userId)
                 .orElseThrow(() -> new BusinessException(ErrorCode.PET_NOT_FOUND));
 
         UUID breedId = current.breedId();
@@ -102,6 +134,16 @@ public class PetService {
         String sex = request.getSex() != null ? request.getSex() : current.sex();
         String status = request.getStatus() != null ? request.getStatus() : current.status();
 
+        // Three-state avatar: absent → carry the stored id through; explicit
+        // null → clear; value → validate then set.
+        UUID avatarAssetId = current.avatarAssetId();
+        if (request.isAvatarAssetIdPresent()) {
+            avatarAssetId = request.getAvatarAssetId();
+            if (avatarAssetId != null) {
+                requireOwnReadyAvatarAsset(userId, avatarAssetId);
+            }
+        }
+
         int updated;
         try {
             updated = petRepository.updateWithVersion(
@@ -120,7 +162,8 @@ public class PetService {
                             ? trimOrNull(request.getMicrochipNo()) : current.microchipNo(),
                     request.getSterilizedOn() != null
                             ? request.getSterilizedOn() : current.sterilizedOn(),
-                    status);
+                    status,
+                    avatarAssetId);
         } catch (DuplicateKeyException e) {
             throw new BusinessException(ErrorCode.MICROCHIP_EXISTS);
         }
@@ -129,8 +172,34 @@ public class PetService {
             // missed conditional update means the version is stale.
             throw new BusinessException(ErrorCode.VERSION_CONFLICT);
         }
-        return petRepository.findByIdForUser(petId, userId)
-                .orElseThrow(() -> new BusinessException(ErrorCode.INTERNAL_ERROR));
+        return toResponse(petRepository.findByIdForUser(petId, userId)
+                .orElseThrow(() -> new BusinessException(ErrorCode.INTERNAL_ERROR)));
+    }
+
+    /**
+     * MANAGE for anything that edits the pet profile, WRITE when the request
+     * touches nothing but the avatar (ADR-022). A body carrying only
+     * {@code version} keeps the historical MANAGE level — it is a
+     * profile-shaped no-op, not an avatar edit.
+     */
+    private static AccessLevel requiredLevel(UpdatePetRequest request) {
+        boolean avatarOnly = request.isAvatarAssetIdPresent() && !request.touchesProfileFields();
+        return avatarOnly ? AccessLevel.WRITE : AccessLevel.MANAGE;
+    }
+
+    private void requireOwnReadyAvatarAsset(UUID userId, UUID assetId) {
+        MediaAssetRef asset = mediaAssetGateway.findById(assetId)
+                .orElseThrow(() -> new BusinessException(ErrorCode.MEDIA_NOT_FOUND));
+        if (!userId.equals(asset.ownerUserId()) || "deleted".equals(asset.status())) {
+            throw new BusinessException(ErrorCode.MEDIA_NOT_FOUND);
+        }
+        if (!AVATAR_PURPOSE.equals(asset.purpose())) {
+            throw new BusinessException(ErrorCode.MEDIA_NOT_FOUND,
+                    "该媒体资源的用途不是 " + AVATAR_PURPOSE + "，不能作为宠物头像");
+        }
+        if (!"ready".equals(asset.status())) {
+            throw new BusinessException(ErrorCode.MEDIA_NOT_READY);
+        }
     }
 
     /**
@@ -156,6 +225,33 @@ public class PetService {
         }
     }
 
+    /**
+     * Signs the avatar URL fresh on every response (never cached, never
+     * persisted) and drops the storage coordinates — the DTO exposes a URL,
+     * not a bucket layout.
+     */
+    private PetResponse toResponse(PetRow row) {
+        return new PetResponse(
+                row.id(),
+                row.name(),
+                row.species(),
+                row.breedId(),
+                row.breedDisplayName(),
+                row.customBreedName(),
+                row.sex(),
+                row.birthDate(),
+                row.birthDateEstimated(),
+                row.personality(),
+                row.microchipNo(),
+                row.sterilizedOn(),
+                row.status(),
+                mediaUrlSigner.signGet(row.avatarBucket(), row.avatarObjectKey()),
+                row.myRole(),
+                row.createdAt(),
+                row.updatedAt(),
+                row.version());
+    }
+
     private static String trimOrNull(String value) {
         if (value == null) {
             return null;

patbond-pet/src/main/resources/application.yml.sample

@@ -19,3 +19,12 @@ patbond:
     # 值可以是 PEM 文件路径，也可以是内联 PEM 内容（以 -----BEGIN 开头）。
     # 私钥只给 patbond-auth，绝不入库。
     public-key: ${PATBOND_JWT_PUBLIC_KEY:}
+  media:
+    # 媒体读取侧（ADR-016 定型：私有桶 + 预签名 GET）。本服务只做本地 SigV4
+    # 签名计算生成宠物头像访问 URL，从不直连对象存储；写入流程在 patbond-user。
+    # 环境变量与 patbond-user/patbond-community 共用同一组（一套部署一套旋钮）。
+    # public-endpoint 为空时服务照常启动，宠物响应中 avatarUrl 为 null。
+    public-endpoint: ${PATBOND_MINIO_PUBLIC_ENDPOINT:}
+    access-key: ${PATBOND_MINIO_ACCESS_KEY:}
+    secret-key: ${PATBOND_MINIO_SECRET_KEY:}
+    download-ttl: ${PATBOND_MEDIA_DOWNLOAD_TTL:1h}

patbond-pet/src/test/java/com/patbond/patbond/pet/controller/PetAvatarIntegrationTest.java

@@ -0,0 +1,335 @@
+package com.patbond.patbond.pet.controller;
+
+import com.jayway.jsonpath.JsonPath;
+import com.patbond.patbond.pet.support.PetIntegrationTestSupport;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.DynamicPropertyRegistry;
+import org.springframework.test.context.DynamicPropertySource;
+import org.springframework.test.web.servlet.MockMvc;
+
+import java.time.OffsetDateTime;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.hamcrest.Matchers.nullValue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.patch;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+/**
+ * T3.5-05 宠物头像读写：PATCH /api/v1/pets/{petId} 的 {@code avatarAssetId}
+ * 三态（缺省不改 / 显式 null 清空 / 赋值设置），详情与列表的 {@code avatarUrl}
+ * 预签名 GET，以及六类路径 —— 成功 / 参数错（asset 非法四态）/ 不存在（防枚举
+ * 404）/ 无权限（viewer 拒写、caregiver 只能改头像）/ 并发冲突（乐观锁 40902）
+ * / 重放（同版本重放必冲突、新版本重放幂等）。
+ *
+ * <p>预签名 GET 是纯本地 SigV4 计算，故这里用占位端点与占位凭证即可断言 URL
+ * 形态（与 patbond-community 的 PostApiTestBase 同先例），无需 MinIO 容器；
+ * 「签名真能下载」的实证由 user 模块的 MeAvatarSigningIntegrationTest 承担。</p>
+ */
+class PetAvatarIntegrationTest extends PetIntegrationTestSupport {
+
+    private static final String SIGNED_PREFIX = "http://127.0.0.1:9000/patbond-media/pet_avatar/";
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @DynamicPropertySource
+    static void wireMediaSigning(DynamicPropertyRegistry registry) {
+        // 占位值（dummy）：仅用于本地 SigV4 计算，不连任何真实存储
+        registry.add("patbond.media.public-endpoint", () -> "http://127.0.0.1:9000");
+        registry.add("patbond.media.access-key", () -> "test-access-key");
+        registry.add("patbond.media.secret-key", () -> "test-secret-key");
+    }
+
+    // ---- helpers -------------------------------------------------------
+
+    private String createPetAs(UUID ownerId) throws Exception {
+        String body = mockMvc.perform(post("/api/v1/pets")
+                        .header("Authorization", "Bearer " + tokenFor(ownerId))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("""
+                                {"name":"头像猫","species":"cat","sex":"female",
+                                 "customBreedName":"狸花"}
+                                """))
+                .andExpect(status().isCreated())
+                // 新建宠物尚无头像
+                .andExpect(jsonPath("$.data.avatarUrl").value(nullValue()))
+                .andReturn().getResponse().getContentAsString();
+        return JsonPath.read(body, "$.data.id");
+    }
+
+    /** 一枚 media.assets 行，用途/状态/归属可控（模拟 T3-03 上传的产物）。 */
+    private UUID insertAsset(UUID ownerUserId, String purpose, String status) {
+        UUID id = UUID.randomUUID();
+        jdbcClient.sql("""
+                        INSERT INTO media.assets
+                            (id, owner_user_id, kind, purpose, storage_type, bucket, object_key,
+                             mime_type, byte_size, status, ready_at, deleted_at)
+                        VALUES (:id, :owner, 'image', :purpose, 'object', 'patbond-media',
+                                :objectKey, 'image/jpeg', 2048, :status, :readyAt, :deletedAt)
+                        """)
+                .param("id", id)
+                .param("owner", ownerUserId)
+                .param("purpose", purpose)
+                .param("objectKey", purpose + "/2026/09/" + id)
+                .param("status", status)
+                .param("readyAt", "ready".equals(status) ? OffsetDateTime.now() : null)
+                // ck_media_deleted：status='deleted' 必带 deleted_at
+                .param("deletedAt", "deleted".equals(status) ? OffsetDateTime.now() : null)
+                .update();
+        return id;
+    }
+
+    private UUID readyPetAvatar(UUID ownerUserId) {
+        return insertAsset(ownerUserId, "pet_avatar", "ready");
+    }
+
+    private String patchPet(UUID actor, String petId, String body, int expectedStatus)
+            throws Exception {
+        return mockMvc.perform(patch("/api/v1/pets/{id}", petId)
+                        .header("Authorization", "Bearer " + tokenFor(actor))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(body))
+                .andExpect(status().is(expectedStatus))
+                .andReturn().getResponse().getContentAsString();
+    }
+
+    private void patchPetExpectingCode(UUID actor, String petId, String body,
+                                       int httpStatus, int bizCode) throws Exception {
+        mockMvc.perform(patch("/api/v1/pets/{id}", petId)
+                        .header("Authorization", "Bearer " + tokenFor(actor))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(body))
+                .andExpect(status().is(httpStatus))
+                .andExpect(jsonPath("$.code").value(bizCode));
+    }
+
+    private static String setAvatarBody(int version, UUID assetId) {
+        return "{\"version\":%d,\"avatarAssetId\":\"%s\"}".formatted(version, assetId);
+    }
+
+    private String detail(UUID actor, String petId) throws Exception {
+        return mockMvc.perform(get("/api/v1/pets/{id}", petId)
+                        .header("Authorization", "Bearer " + tokenFor(actor)))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+    }
+
+    private UUID dbAvatarAssetId(String petId) {
+        return jdbcClient.sql("SELECT avatar_asset_id FROM pet_health.pets WHERE id = :id")
+                .param("id", UUID.fromString(petId))
+                .query(UUID.class)
+                .optional()
+                .orElse(null);
+    }
+
+    // ---- 成功路径 -------------------------------------------------------
+
+    @Test
+    void ownerSetsAvatarAndDetailAndListBothCarryASignedUrl() throws Exception {
+        UUID owner = newUser("pet_avatar_owner");
+        String petId = createPetAs(owner);
+        UUID asset = readyPetAvatar(owner);
+
+        String patched = patchPet(owner, petId, setAvatarBody(0, asset), 200);
+        assertThat((String) JsonPath.read(patched, "$.data.avatarUrl"))
+                .startsWith(SIGNED_PREFIX)
+                .contains("X-Amz-Signature=");
+        assertThat(dbAvatarAssetId(petId)).isEqualTo(asset);
+        // 头像也吃乐观锁：写入后 version 前进
+        assertThat((int) JsonPath.read(patched, "$.data.version")).isEqualTo(1);
+
+        assertThat((String) JsonPath.read(detail(owner, petId), "$.data.avatarUrl"))
+                .startsWith(SIGNED_PREFIX);
+
+        String listBody = mockMvc.perform(get("/api/v1/pets")
+                        .header("Authorization", "Bearer " + tokenFor(owner)))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+        List<Map<String, Object>> pets = JsonPath.read(listBody, "$.data");
+        assertThat((String) pets.get(0).get("avatarUrl")).startsWith(SIGNED_PREFIX);
+    }
+
+    @Test
+    void clearsAvatarWithAnExplicitNull() throws Exception {
+        UUID owner = newUser("pet_avatar_clear");
+        String petId = createPetAs(owner);
+        patchPet(owner, petId, setAvatarBody(0, readyPetAvatar(owner)), 200);
+
+        String cleared = patchPet(owner, petId, "{\"version\":1,\"avatarAssetId\":null}", 200);
+        assertThat((Object) JsonPath.read(cleared, "$.data.avatarUrl")).isNull();
+        assertThat(dbAvatarAssetId(petId)).isNull();
+    }
+
+    /**
+     * 缺省即不改：只改名字的 PATCH 不得把头像顺手清掉（这正是三态语义存在的
+     * 理由——若 null 与缺省同义，就无法既保留又能清空）。
+     */
+    @Test
+    void absentAvatarFieldLeavesItUntouched() throws Exception {
+        UUID owner = newUser("pet_avatar_absent");
+        String petId = createPetAs(owner);
+        UUID asset = readyPetAvatar(owner);
+        patchPet(owner, petId, setAvatarBody(0, asset), 200);
+
+        String renamed = patchPet(owner, petId, "{\"version\":1,\"name\":\"改个名\"}", 200);
+        assertThat((String) JsonPath.read(renamed, "$.data.name")).isEqualTo("改个名");
+        assertThat((String) JsonPath.read(renamed, "$.data.avatarUrl")).startsWith(SIGNED_PREFIX);
+        assertThat(dbAvatarAssetId(petId)).isEqualTo(asset);
+    }
+
+    /**
+     * 指针在、资源却退出 ready（如后台清理置 failed）：URL 降级为 null 而不是
+     * 签一个下载必 404 的地址；数据库指针本身保留，不做隐式清理。
+     */
+    @Test
+    void avatarUrlDegradesToNullWhenTheAssetLeavesReady() throws Exception {
+        UUID owner = newUser("pet_avatar_degrade");
+        String petId = createPetAs(owner);
+        UUID asset = readyPetAvatar(owner);
+        patchPet(owner, petId, setAvatarBody(0, asset), 200);
+
+        jdbcClient.sql("UPDATE media.assets SET status = 'failed' WHERE id = :id")
+                .param("id", asset)
+                .update();
+
+        assertThat((Object) JsonPath.read(detail(owner, petId), "$.data.avatarUrl")).isNull();
+        assertThat(dbAvatarAssetId(petId)).isEqualTo(asset);
+    }
+
+    // ---- 权限：WRITE 档（ADR-022） ---------------------------------------
+
+    /**
+     * caregiver 可改头像（WRITE 档：头像属日常照护信息，与体重/疫苗同档），
+     * 但资料本体仍是 MANAGE —— 同一端点按「本次请求碰了哪些字段」定档。
+     */
+    @Test
+    void caregiverMayChangeTheAvatarButNotTheProfile() throws Exception {
+        UUID owner = newUser("pet_avatar_owner2");
+        UUID caregiver = newUser("pet_avatar_caregiver");
+        String petId = createPetAs(owner);
+        grantRole(UUID.fromString(petId), caregiver, "caregiver");
+        UUID asset = readyPetAvatar(caregiver);
+
+        String patched = patchPet(caregiver, petId, setAvatarBody(0, asset), 200);
+        assertThat((String) JsonPath.read(patched, "$.data.avatarUrl")).startsWith(SIGNED_PREFIX);
+
+        // 资料字段仍需 MANAGE
+        patchPetExpectingCode(caregiver, petId, "{\"version\":1,\"name\":\"照护人改名\"}", 403, 40300);
+        // 头像 + 资料混合按更严的那一半判（MANAGE）
+        patchPetExpectingCode(caregiver, petId,
+                "{\"version\":1,\"name\":\"夹带改名\",\"avatarAssetId\":null}", 403, 40300);
+    }
+
+    @Test
+    void viewerCannotChangeTheAvatar() throws Exception {
+        UUID owner = newUser("pet_avatar_owner3");
+        UUID viewer = newUser("pet_avatar_viewer");
+        String petId = createPetAs(owner);
+        grantRole(UUID.fromString(petId), viewer, "viewer");
+        UUID asset = readyPetAvatar(viewer);
+
+        patchPetExpectingCode(viewer, petId, setAvatarBody(0, asset), 403, 40300);
+        assertThat(dbAvatarAssetId(petId)).isNull();
+        // 只读仍可见
+        mockMvc.perform(get("/api/v1/pets/{id}", petId)
+                        .header("Authorization", "Bearer " + tokenFor(viewer)))
+                .andExpect(status().isOk());
+    }
+
+    // ---- 不存在路径（防枚举） --------------------------------------------
+
+    @Test
+    void strangerAndGhostPetAnswerTheSame404() throws Exception {
+        UUID owner = newUser("pet_avatar_owner4");
+        UUID stranger = newUser("pet_avatar_stranger");
+        String petId = createPetAs(owner);
+        UUID asset = readyPetAvatar(stranger);
+
+        patchPetExpectingCode(stranger, petId, setAvatarBody(0, asset), 404, 40401);
+        patchPetExpectingCode(stranger, UUID.randomUUID().toString(),
+                setAvatarBody(0, asset), 404, 40401);
+    }
+
+    // ---- 参数错：asset 非法四态 ------------------------------------------
+
+    @Test
+    void rejectsUnknownForeignOrWrongPurposeAsset() throws Exception {
+        UUID owner = newUser("pet_avatar_asset");
+        UUID stranger = newUser("pet_avatar_assetowner");
+        String petId = createPetAs(owner);
+
+        // 幽灵 id 与他人 asset 同答 40405（防枚举合并）
+        patchPetExpectingCode(owner, petId, setAvatarBody(0, UUID.randomUUID()), 404, 40405);
+        patchPetExpectingCode(owner, petId,
+                setAvatarBody(0, insertAsset(stranger, "pet_avatar", "ready")), 404, 40405);
+        // 用途不符：帖子配图不能当宠物头像
+        patchPetExpectingCode(owner, petId,
+                setAvatarBody(0, insertAsset(owner, "post_image", "ready")), 404, 40405);
+        // 用户头像也不行：两种头像用途各归各
+        patchPetExpectingCode(owner, petId,
+                setAvatarBody(0, insertAsset(owner, "user_avatar", "ready")), 404, 40405);
+        // 已删资源对引用方即不存在
+        patchPetExpectingCode(owner, petId,
+                setAvatarBody(0, insertAsset(owner, "pet_avatar", "deleted")), 404, 40405);
+        assertThat(dbAvatarAssetId(petId)).isNull();
+    }
+
+    @Test
+    void rejectsAssetThatIsNotReadyYet() throws Exception {
+        UUID owner = newUser("pet_avatar_state");
+        String petId = createPetAs(owner);
+
+        patchPetExpectingCode(owner, petId,
+                setAvatarBody(0, insertAsset(owner, "pet_avatar", "uploading")), 422, 42203);
+        patchPetExpectingCode(owner, petId,
+                setAvatarBody(0, insertAsset(owner, "pet_avatar", "failed")), 422, 42203);
+        assertThat(dbAvatarAssetId(petId)).isNull();
+    }
+
+    @Test
+    void rejectsMalformedAvatarAssetIdAndMissingVersion() throws Exception {
+        UUID owner = newUser("pet_avatar_malformed");
+        String petId = createPetAs(owner);
+
+        patchPetExpectingCode(owner, petId,
+                "{\"version\":0,\"avatarAssetId\":\"not-a-uuid\"}", 400, 40000);
+        // version 仍是必填（乐观锁不可绕过），哪怕只改头像
+        patchPetExpectingCode(owner, petId,
+                "{\"avatarAssetId\":\"%s\"}".formatted(readyPetAvatar(owner)), 400, 40000);
+    }
+
+    // ---- 并发冲突与重放 --------------------------------------------------
+
+    /**
+     * 头像写入走同一把乐观锁：拿旧 version 的第二个写者必败 40902（并发冲突），
+     * 而带同一 body 的重放正是「旧 version 再来一次」，因此必须同样冲突——这
+     * 是 pets 域自 M2 起的一致语义，头像不另开后门。
+     */
+    @Test
+    void staleVersionLosesAndReplayOfTheSameBodyConflicts() throws Exception {
+        UUID owner = newUser("pet_avatar_version");
+        String petId = createPetAs(owner);
+        UUID first = readyPetAvatar(owner);
+        UUID second = readyPetAvatar(owner);
+
+        patchPet(owner, petId, setAvatarBody(0, first), 200);
+        // 重放（同 body、同旧 version）→ 40902
+        patchPetExpectingCode(owner, petId, setAvatarBody(0, first), 409, 40902);
+        // 另一个写者拿旧 version 抢改 → 同样 40902
+        patchPetExpectingCode(owner, petId, setAvatarBody(0, second), 409, 40902);
+        assertThat(dbAvatarAssetId(petId)).isEqualTo(first);
+
+        // 用新 version 重放同一头像 → 幂等地仍是这张图（version 继续前进）
+        String again = patchPet(owner, petId, setAvatarBody(1, first), 200);
+        assertThat(dbAvatarAssetId(petId)).isEqualTo(first);
+        assertThat((int) JsonPath.read(again, "$.data.version")).isEqualTo(2);
+    }
+}

patbond-user/src/main/java/com/patbond/patbond/user/controller/MeController.java

@@ -1,34 +1,50 @@
 package com.patbond.patbond.user.controller;
 
 import com.patbond.patbond.common.response.ApiResponse;
-import com.patbond.patbond.common.user.UserProfile;
 import com.patbond.patbond.user.dto.MeResponse;
+import com.patbond.patbond.user.dto.UpdateMeRequest;
 import com.patbond.patbond.user.security.BearerAuthFilter;
-import com.patbond.patbond.user.service.UserService;
+import com.patbond.patbond.user.service.MeProfileService;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PatchMapping;
 import org.springframework.web.bind.annotation.RequestAttribute;
+import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
 
 import java.util.UUID;
 
 /**
- * Public profile endpoint. Authentication happens in BearerAuthFilter (RS256
- * verification against the auth service's public key); by the time this
- * controller runs, the user id attribute is guaranteed to be present.
+ * The account owner's own profile (T3.5-04). Authentication happens in
+ * BearerAuthFilter (RS256 verification against the auth service's public
+ * key); by the time this controller runs, the user id attribute is guaranteed
+ * to be present, so there is no "other user" case here — the resource is
+ * always the caller's own.
+ *
+ * <p>PATCH is intentionally not {@code @Valid}-annotated: the three-state
+ * fields of {@link UpdateMeRequest} (absent / null / value) need
+ * presence-aware checks that bean validation cannot express, so all rules
+ * live in {@link MeProfileService} and answer 400/40000 with a precise
+ * message.</p>
  */
 @RestController
 public class MeController {
 
-    private final UserService userService;
+    private final MeProfileService meProfileService;
 
-    public MeController(UserService userService) {
-        this.userService = userService;
+    public MeController(MeProfileService meProfileService) {
+        this.meProfileService = meProfileService;
     }
 
     @GetMapping("/api/v1/me")
-    public ApiResponse<MeResponse> me(@RequestAttribute(BearerAuthFilter.USER_ID_ATTRIBUTE) UUID userId) {
-        UserProfile profile = userService.getById(userId);
-        return ApiResponse.success(new MeResponse(
-                profile.getId(), profile.getUsername(), profile.getPhone(), profile.getCreatedAt()));
+    public ApiResponse<MeResponse> me(
+            @RequestAttribute(BearerAuthFilter.USER_ID_ATTRIBUTE) UUID userId) {
+        return ApiResponse.success(meProfileService.get(userId));
+    }
+
+    @PatchMapping("/api/v1/me")
+    public ApiResponse<MeResponse> updateMe(
+            @RequestAttribute(BearerAuthFilter.USER_ID_ATTRIBUTE) UUID userId,
+            @RequestBody UpdateMeRequest request) {
+        return ApiResponse.success(meProfileService.update(userId, request));
     }
 }

patbond-user/src/main/java/com/patbond/patbond/user/dto/MeResponse.java

@@ -4,8 +4,25 @@ import java.time.OffsetDateTime;
 import java.util.UUID;
 
 /**
- * Public /api/v1/me payload — exactly the frozen contract fields
- * {userId, username, phone, createdAt}; nothing else leaks out.
+ * The owner's own profile — payload of both GET and PATCH /api/v1/me
+ * (T3.5-04).
+ *
+ * <p>{@code nickname} is the RAW stored value and is null when the user never
+ * set one: unlike {@link PublicProfileResponse}, this endpoint deliberately
+ * does NOT apply the nickname→username fallback. /me is the editing surface
+ * of the account owner, so it must report what is actually stored; a fallback
+ * here would prefill the edit form with a username the user never chose and
+ * the next save would silently promote it into a real nickname. The display
+ * fallback belongs where display happens — /internal/users/profiles for other
+ * people's view (SQL COALESCE, T3-05) and the client's own greeting.</p>
+ *
+ * <p>{@code avatarUrl} is a freshly signed presigned GET (private bucket,
+ * T3-03 定型): it EXPIRES and must never be persisted client-side. It is null
+ * both when no avatar is set and when the avatar asset is not (or no longer)
+ * ready, so the client's "has an avatar" test is exactly "avatarUrl != null".
+ * The asset id itself is deliberately not echoed — the client only ever
+ * writes it (PATCH) and renders the URL.</p>
  */
-public record MeResponse(UUID userId, String username, String phone, OffsetDateTime createdAt) {
+public record MeResponse(UUID userId, String username, String nickname, String phone,
+                         String avatarUrl, OffsetDateTime createdAt) {
 }

patbond-user/src/main/java/com/patbond/patbond/user/dto/UpdateMeRequest.java

@@ -0,0 +1,67 @@
+package com.patbond.patbond.user.dto;
+
+import java.util.UUID;
+
+/**
+ * PATCH /api/v1/me (T3.5-04). Partial update with an EXPLICIT三态 semantics
+ * per field, which is what the avatar and nickname features need and what the
+ * pets domain's "absent-or-null means unchanged" convention (M2, see
+ * UpdatePetRequest) cannot express:
+ *
+ * <ul>
+ *   <li><b>key absent</b> → leave the column untouched;</li>
+ *   <li><b>key present with null</b> → clear the column (remove the nickname /
+ *       remove the avatar);</li>
+ *   <li><b>key present with a value</b> → set it.</li>
+ * </ul>
+ *
+ * <p>Why the difference from pets: name/species/sex have no meaningful empty
+ * state (their CHECK constraints forbid it), so M2 could afford to conflate
+ * null with absent. A nickname and an avatar are genuinely optional and
+ * "remove what I set" is a first-class user action — with only two states
+ * there would be no way to express it at all. Presence is tracked by the
+ * setters: Jackson calls a setter exactly when the JSON key is present,
+ * including when its value is null.</p>
+ *
+ * <p>A body that touches neither field is rejected with 400/40000 rather than
+ * answering a silent 200 — an empty PATCH is a client bug, not an intent.</p>
+ */
+public class UpdateMeRequest {
+
+    private String nickname;
+    private boolean nicknamePresent;
+
+    private UUID avatarAssetId;
+    private boolean avatarAssetIdPresent;
+
+    public String getNickname() {
+        return nickname;
+    }
+
+    public void setNickname(String nickname) {
+        this.nickname = nickname;
+        this.nicknamePresent = true;
+    }
+
+    public boolean isNicknamePresent() {
+        return nicknamePresent;
+    }
+
+    public UUID getAvatarAssetId() {
+        return avatarAssetId;
+    }
+
+    public void setAvatarAssetId(UUID avatarAssetId) {
+        this.avatarAssetId = avatarAssetId;
+        this.avatarAssetIdPresent = true;
+    }
+
+    public boolean isAvatarAssetIdPresent() {
+        return avatarAssetIdPresent;
+    }
+
+    /** True when the body carries no updatable field at all. */
+    public boolean isEmptyPatch() {
+        return !nicknamePresent && !avatarAssetIdPresent;
+    }
+}

patbond-user/src/main/java/com/patbond/patbond/user/media/MediaProperties.java

@@ -54,8 +54,16 @@ public class MediaProperties {
     /** Mime whitelist for kind=image (M3: jpeg/png/webp). */
     private List<String> allowedMimeTypes = List.of("image/jpeg", "image/png", "image/webp");
 
-    /** Purpose whitelist; decides the objectKey prefix. M3: post_image. */
-    private List<String> allowedPurposes = List.of("post_image");
+    /**
+     * Purpose whitelist; decides the objectKey prefix. M3 shipped
+     * {@code post_image}; M3.5 adds the two avatar purposes (ADR-022 —
+     * media.assets.purpose has no CHECK constraint, so a new use case is a
+     * configuration + contract-enum change, never a migration). The purpose
+     * is also the referencing side's type check: only a {@code user_avatar}
+     * asset may become a user avatar, only a {@code pet_avatar} asset a pet
+     * avatar, so a post image can never be silently reused as an avatar.
+     */
+    private List<String> allowedPurposes = List.of("post_image", "user_avatar", "pet_avatar");
 
     public String getEndpoint() {
         return endpoint;

patbond-user/src/main/java/com/patbond/patbond/user/repository/UserRepository.java

@@ -4,6 +4,7 @@ import org.springframework.jdbc.core.simple.JdbcClient;
 import org.springframework.stereotype.Repository;
 
 import java.time.OffsetDateTime;
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Optional;
@@ -42,6 +43,16 @@ public class UserRepository {
     public record PublicProfileRow(UUID id, String nickname, UUID avatarAssetId) {
     }
 
+    /**
+     * Owner's-own-profile projection for /api/v1/me (T3.5-04). {@code nickname}
+     * is the RAW column — no username fallback here (see MeResponse for why);
+     * {@code avatarObjectKey} is already narrowed to a READY asset, so the
+     * caller only has to sign it.
+     */
+    public record MeRow(UUID id, String username, String nickname, String phone,
+                        String avatarObjectKey, OffsetDateTime createdAt) {
+    }
+
     /** Inserts the user row; created_at/updated_at come from the DB defaults. */
     public OffsetDateTime insertUser(UUID id, String username, String nickname, String phone) {
         return jdbcClient.sql("""
@@ -117,6 +128,69 @@ public class UserRepository {
                 .list();
     }
 
+    /**
+     * The owner's own profile plus the object key of a READY avatar asset.
+     * The LEFT JOIN carries the readiness condition, so a dangling or
+     * still-uploading avatar simply yields a null key (→ {@code avatarUrl:
+     * null}) instead of a broken signed URL.
+     */
+    public Optional<MeRow> findMeById(UUID id) {
+        return jdbcClient.sql("""
+                        SELECT u.id, u.username::text AS username, u.nickname, u.phone_e164,
+                               u.created_at, a.object_key AS avatar_object_key
+                        FROM identity.users u
+                        LEFT JOIN media.assets a
+                               ON a.id = u.avatar_asset_id AND a.status = 'ready'
+                        WHERE u.id = :id AND u.deleted_at IS NULL
+                        """)
+                .param("id", id)
+                .query((rs, rowNum) -> new MeRow(
+                        rs.getObject("id", UUID.class),
+                        rs.getString("username"),
+                        rs.getString("nickname"),
+                        rs.getString("phone_e164"),
+                        rs.getString("avatar_object_key"),
+                        rs.getObject("created_at", OffsetDateTime.class)))
+                .optional();
+    }
+
+    /**
+     * Column-selective profile update for PATCH /api/v1/me: only the columns
+     * the request actually carried appear in the SET list. This is
+     * deliberately NOT a read-merge-write — two concurrent PATCHes, one
+     * changing the nickname and one the avatar, both survive, whereas a
+     * merged full-row write would let the later one silently revert the
+     * other's field. /me has a single legitimate writer (the account owner),
+     * so no optimistic-lock version is exposed; last write wins per column.
+     *
+     * @return rows updated — 0 means the user is gone (or soft-deleted)
+     */
+    public int updateOwnProfile(UUID id, boolean setNickname, String nickname,
+                                boolean setAvatarAssetId, UUID avatarAssetId) {
+        List<String> assignments = new ArrayList<>(2);
+        if (setNickname) {
+            assignments.add("nickname = :nickname");
+        }
+        if (setAvatarAssetId) {
+            assignments.add("avatar_asset_id = :avatarAssetId");
+        }
+        if (assignments.isEmpty()) {
+            throw new IllegalArgumentException("updateOwnProfile 需至少一个待更新列");
+        }
+        JdbcClient.StatementSpec spec = jdbcClient.sql("""
+                        UPDATE identity.users SET %s
+                        WHERE id = :id AND deleted_at IS NULL
+                        """.formatted(String.join(", ", assignments)))
+                .param("id", id);
+        if (setNickname) {
+            spec = spec.param("nickname", nickname);
+        }
+        if (setAvatarAssetId) {
+            spec = spec.param("avatarAssetId", avatarAssetId);
+        }
+        return spec.update();
+    }
+
     public Optional<AuthRow> findAuthByUsername(String username) {
         return jdbcClient.sql("""
                         SELECT u.id, u.username::text AS username, u.nickname, c.password_hash, c.locked_until

patbond-user/src/main/java/com/patbond/patbond/user/service/MeProfileService.java

@@ -0,0 +1,152 @@
+package com.patbond.patbond.user.service;
+
+import com.patbond.patbond.common.error.BusinessException;
+import com.patbond.patbond.common.error.ErrorCode;
+import com.patbond.patbond.user.dto.MeResponse;
+import com.patbond.patbond.user.dto.UpdateMeRequest;
+import com.patbond.patbond.user.media.MediaAssetRepository;
+import com.patbond.patbond.user.media.MediaProperties;
+import com.patbond.patbond.user.media.ObjectStorage;
+import com.patbond.patbond.user.repository.UserRepository;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.UUID;
+
+/**
+ * The account owner's own profile: GET and PATCH /api/v1/me (T3.5-04).
+ *
+ * <p>Semantics frozen with this ticket:
+ * <ul>
+ *   <li><b>No nickname fallback on /me</b> — the raw stored value, null when
+ *       unset (rationale in {@link MeResponse}). The fallback stays in
+ *       /internal/users/profiles' SQL, where other people's display name is
+ *       produced.</li>
+ *   <li><b>PATCH is三态 per field</b> — absent = unchanged, explicit null =
+ *       clear, value = set (see {@link UpdateMeRequest}). An empty patch is
+ *       400/40000.</li>
+ *   <li><b>nickname validation mirrors ck_users_nickname</b> — trimmed, 1..32
+ *       CODE POINTS (PostgreSQL char_length counts code points, so a Java
+ *       String.length() bound would reject 32 emoji the database accepts);
+ *       whitespace-only is 400/40000, never an implicit clear, so clearing is
+ *       expressible exactly one way.</li>
+ *   <li><b>avatarAssetId validation mirrors the T3-03 referencing protocol</b>
+ *       — unknown / someone else's / deleted asset → 404/40405 (one merged
+ *       anti-enumeration answer); the caller's own asset with the wrong
+ *       purpose → 404/40405 as well (from the avatar domain's point of view a
+ *       post image is not an avatar; no enumeration risk, since the branch is
+ *       only reachable for assets the caller owns, so the message may be
+ *       specific); the caller's own user_avatar asset still uploading or
+ *       failed → 422/42203.</li>
+ * </ul>
+ *
+ * <p>No optimistic lock is exposed: /me has one legitimate writer and the
+ * update is column-selective, so concurrent nickname/avatar patches cannot
+ * clobber each other (see {@link UserRepository#updateOwnProfile}).</p>
+ */
+@Service
+public class MeProfileService {
+
+    /** The only media purpose acceptable as a user avatar (ADR-022). */
+    private static final String AVATAR_PURPOSE = "user_avatar";
+
+    private static final int NICKNAME_MAX_CODE_POINTS = 32;
+
+    private final UserRepository userRepository;
+    private final MediaAssetRepository mediaAssetRepository;
+    private final ObjectStorage objectStorage;
+    private final MediaProperties mediaProperties;
+
+    public MeProfileService(UserRepository userRepository,
+                            MediaAssetRepository mediaAssetRepository,
+                            ObjectStorage objectStorage,
+                            MediaProperties mediaProperties) {
+        this.userRepository = userRepository;
+        this.mediaAssetRepository = mediaAssetRepository;
+        this.objectStorage = objectStorage;
+        this.mediaProperties = mediaProperties;
+    }
+
+    @Transactional(readOnly = true)
+    public MeResponse get(UUID userId) {
+        return toResponse(userRepository.findMeById(userId)
+                .orElseThrow(() -> new BusinessException(ErrorCode.USER_NOT_FOUND)));
+    }
+
+    @Transactional
+    public MeResponse update(UUID userId, UpdateMeRequest request) {
+        if (request.isEmptyPatch()) {
+            throw new BusinessException(ErrorCode.VALIDATION_ERROR,
+                    "请至少提交一个可更新字段：nickname 或 avatarAssetId");
+        }
+
+        String nickname = null;
+        if (request.isNicknamePresent() && request.getNickname() != null) {
+            nickname = requireNickname(request.getNickname());
+        }
+        if (request.isAvatarAssetIdPresent() && request.getAvatarAssetId() != null) {
+            requireOwnReadyAvatarAsset(userId, request.getAvatarAssetId());
+        }
+
+        int updated = userRepository.updateOwnProfile(userId,
+                request.isNicknamePresent(), nickname,
+                request.isAvatarAssetIdPresent(), request.getAvatarAssetId());
+        if (updated == 0) {
+            // The token is valid but the account is gone (or 注销) — same
+            // answer as a GET of a soft-deleted user.
+            throw new BusinessException(ErrorCode.USER_NOT_FOUND);
+        }
+        return get(userId);
+    }
+
+    /**
+     * Trims like {@code btrim} and enforces the ck_users_nickname width. A
+     * blank-after-trim value is a validation error rather than a clear: an
+     * explicit JSON null is the single, unambiguous way to remove a nickname.
+     */
+    private static String requireNickname(String raw) {
+        String trimmed = raw.trim();
+        int codePoints = trimmed.codePointCount(0, trimmed.length());
+        if (codePoints < 1 || codePoints > NICKNAME_MAX_CODE_POINTS) {
+            throw new BusinessException(ErrorCode.VALIDATION_ERROR,
+                    "nickname 去除首尾空白后长度须在 1~" + NICKNAME_MAX_CODE_POINTS
+                            + " 字符；如需清空请显式提交 null");
+        }
+        return trimmed;
+    }
+
+    private void requireOwnReadyAvatarAsset(UUID userId, UUID assetId) {
+        MediaAssetRepository.AssetRow asset = mediaAssetRepository
+                .findByIdAndOwner(assetId, userId)
+                .orElseThrow(() -> new BusinessException(ErrorCode.MEDIA_NOT_FOUND));
+        if ("deleted".equals(asset.status())) {
+            throw new BusinessException(ErrorCode.MEDIA_NOT_FOUND);
+        }
+        if (!AVATAR_PURPOSE.equals(asset.purpose())) {
+            throw new BusinessException(ErrorCode.MEDIA_NOT_FOUND,
+                    "该媒体资源的用途不是 " + AVATAR_PURPOSE + "，不能作为头像");
+        }
+        if (!"ready".equals(asset.status())) {
+            throw new BusinessException(ErrorCode.MEDIA_NOT_READY);
+        }
+    }
+
+    private MeResponse toResponse(UserRepository.MeRow row) {
+        return new MeResponse(row.id(), row.username(), row.nickname(), row.phone(),
+                signAvatar(row.avatarObjectKey()), row.createdAt());
+    }
+
+    /**
+     * Signs a short-lived GET for the avatar object. Storage being
+     * unconfigured degrades to {@code avatarUrl: null} (same precedent as the
+     * community read side and the missing JWT public key) instead of failing
+     * the whole profile read — the condition mirrors MediaStorageConfig's.
+     */
+    private String signAvatar(String objectKey) {
+        String endpoint = mediaProperties.getEndpoint();
+        if (objectKey == null || endpoint == null || endpoint.isBlank()) {
+            return null;
+        }
+        return objectStorage.presignGet(objectKey, mediaProperties.getDownloadTtl());
+    }
+}

patbond-user/src/main/resources/application.yml.sample

@@ -53,10 +53,10 @@ patbond:
     # 预签名 PUT 凭据与 GET URL 的有效期
     upload-ttl: ${PATBOND_MEDIA_UPLOAD_TTL:10m}
     download-ttl: ${PATBOND_MEDIA_DOWNLOAD_TTL:1h}
-    # 单文件上限（字节）与 mime/purpose 白名单（M3 首版：图片、帖子配图）
+    # 单文件上限（字节）与 mime/purpose 白名单（M3.5：帖子配图 + 用户/宠物头像）
     max-byte-size: ${PATBOND_MEDIA_MAX_BYTE_SIZE:10485760}
     allowed-mime-types: image/jpeg,image/png,image/webp
-    allowed-purposes: post_image
+    allowed-purposes: post_image,user_avatar,pet_avatar
 
 # Development seed data (regions reference rows) is opt-in. To load it,
 # activate a dev profile that widens the Flyway locations:

patbond-user/src/test/java/com/patbond/patbond/user/controller/MeAvatarSigningIntegrationTest.java

@@ -0,0 +1,217 @@
+package com.patbond.patbond.user.controller;
+
+import com.jayway.jsonpath.JsonPath;
+import com.patbond.patbond.user.TestcontainersConfiguration;
+import com.patbond.patbond.user.support.TestJwtKeys;
+import com.patbond.patbond.user.support.UuidV7;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Import;
+import org.springframework.http.MediaType;
+import org.springframework.jdbc.core.simple.JdbcClient;
+import org.springframework.test.context.DynamicPropertyRegistry;
+import org.springframework.test.context.DynamicPropertySource;
+import org.springframework.test.web.servlet.MockMvc;
+import org.testcontainers.containers.MinIOContainer;
+import org.testcontainers.utility.DockerImageName;
+
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.time.Duration;
+import java.util.Map;
+import java.util.UUID;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.patch;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+/**
+ * T3.5-04 头像全链路（真实 MinIO Testcontainer，镜像 tag 与 compose 一致）：
+ * 以 {@code purpose=user_avatar} 创建上传 → 凭据直传 → complete 置 ready →
+ * PATCH /me 挂头像 → GET /me 的 {@code avatarUrl} 是可真实下载的预签名 GET →
+ * 清空后回到 null。同时实证新加入白名单的 user_avatar 用途端到端可用，以及
+ * 「真实未就绪 asset 被拒 42203」（非 SQL 造数据的那一版）。
+ */
+@SpringBootTest
+@AutoConfigureMockMvc
+@Import(TestcontainersConfiguration.class)
+class MeAvatarSigningIntegrationTest {
+
+    /** 与 docker-compose.yml 的 minio 服务钉同一 tag（ADR-016 三环境零分叉）。 */
+    private static final MinIOContainer MINIO = new MinIOContainer(
+            DockerImageName.parse("minio/minio:RELEASE.2025-04-22T22-12-26Z"))
+            // 值仅为测试占位（dummy），非真实凭证
+            .withUserName("minio-dummy-access")
+            .withPassword("minio-dummy-secret");
+
+    private static final HttpClient HTTP = HttpClient.newBuilder()
+            .connectTimeout(Duration.ofSeconds(10))
+            .build();
+
+    private static final byte[] FAKE_JPEG = fakeJpeg();
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private JdbcClient jdbcClient;
+
+    @DynamicPropertySource
+    static void wireMedia(DynamicPropertyRegistry registry) {
+        MINIO.start();
+        registry.add("patbond.jwt.public-key", TestJwtKeys::publicPem);
+        registry.add("patbond.media.endpoint", MINIO::getS3URL);
+        registry.add("patbond.media.access-key", MINIO::getUserName);
+        registry.add("patbond.media.secret-key", MINIO::getPassword);
+    }
+
+    private static byte[] fakeJpeg() {
+        byte[] bytes = new byte[1024];
+        for (int i = 0; i < bytes.length; i++) {
+            bytes[i] = (byte) (i * 17);
+        }
+        bytes[0] = (byte) 0xFF;
+        bytes[1] = (byte) 0xD8; // JPEG SOI
+        return bytes;
+    }
+
+    private UUID newUser(String username) {
+        UUID id = UuidV7.generate();
+        jdbcClient.sql("INSERT INTO identity.users (id, username) VALUES (:id, :username)")
+                .param("id", id)
+                .param("username", username)
+                .update();
+        return id;
+    }
+
+    private static String bearer(UUID userId) {
+        return "Bearer " + TestJwtKeys.accessToken(
+                TestJwtKeys.KEY_PAIR.getPrivate(), userId, Duration.ofMinutes(15));
+    }
+
+    /** 以 user_avatar 用途申请上传凭据（本单新加入白名单）。 */
+    private String createAvatarUpload(UUID user) throws Exception {
+        return mockMvc.perform(post("/api/v1/media/uploads")
+                        .header("Authorization", bearer(user))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("""
+                                {"kind":"image","purpose":"user_avatar",
+                                 "mimeType":"image/jpeg","byteSize":%d}
+                                """.formatted(FAKE_JPEG.length)))
+                .andExpect(status().isCreated())
+                .andExpect(jsonPath("$.data.assetId").isNotEmpty())
+                .andReturn().getResponse().getContentAsString();
+    }
+
+    private void directPut(String createdBody) throws Exception {
+        String uploadUrl = JsonPath.read(createdBody, "$.data.uploadUrl");
+        Map<String, String> headers = JsonPath.read(createdBody, "$.data.requiredHeaders");
+        HttpRequest.Builder put = HttpRequest.newBuilder(URI.create(uploadUrl))
+                .PUT(HttpRequest.BodyPublishers.ofByteArray(FAKE_JPEG));
+        headers.forEach(put::header);
+        assertThat(HTTP.send(put.build(), HttpResponse.BodyHandlers.discarding()).statusCode())
+                .isEqualTo(200);
+    }
+
+    /** 走完 T3-03 两步上传，返回 ready 的 assetId。 */
+    private String uploadReadyAvatar(UUID user) throws Exception {
+        String created = createAvatarUpload(user);
+        String assetId = JsonPath.read(created, "$.data.assetId");
+        directPut(created);
+        mockMvc.perform(post("/api/v1/media/uploads/{assetId}/complete", assetId)
+                        .header("Authorization", bearer(user)))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.data.status").value("ready"));
+        return assetId;
+    }
+
+    @Test
+    void avatarUrlIsAFreshPresignedGetThatActuallyDownloads() throws Exception {
+        UUID user = newUser("avatar_signed");
+        String assetId = uploadReadyAvatar(user);
+
+        String patched = mockMvc.perform(patch("/api/v1/me")
+                        .header("Authorization", bearer(user))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"avatarAssetId\":\"%s\"}".formatted(assetId)))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+
+        String avatarUrl = JsonPath.read(patched, "$.data.avatarUrl");
+        assertThat(avatarUrl)
+                .startsWith(MINIO.getS3URL() + "/patbond-media/user_avatar/")
+                .contains("X-Amz-Signature=");
+
+        // 真实下载：签名有效，私有桶靠签名而非公开读
+        HttpResponse<byte[]> download = HTTP.send(
+                HttpRequest.newBuilder(URI.create(avatarUrl)).GET().build(),
+                HttpResponse.BodyHandlers.ofByteArray());
+        assertThat(download.statusCode()).isEqualTo(200);
+        assertThat(download.body()).isEqualTo(FAKE_JPEG);
+
+        // GET /me 每次重新签发（URL 会过期，客户端不得持久化）
+        String fetched = mockMvc.perform(get("/api/v1/me").header("Authorization", bearer(user)))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+        assertThat((String) JsonPath.read(fetched, "$.data.avatarUrl"))
+                .startsWith(MINIO.getS3URL() + "/patbond-media/user_avatar/");
+
+        // 清空后回到 null
+        String cleared = mockMvc.perform(patch("/api/v1/me")
+                        .header("Authorization", bearer(user))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"avatarAssetId\":null}"))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+        assertThat((Object) JsonPath.read(cleared, "$.data.avatarUrl")).isNull();
+    }
+
+    /**
+     * 真实的「凭据已发但还没直传」状态：asset 存在、属本人、用途正确，但仍是
+     * uploading —— 引用侧必须 422/42203，不能挂上一个下载会 404 的头像。
+     */
+    @Test
+    void refusesAnAvatarAssetWhoseUploadNeverCompleted() throws Exception {
+        UUID user = newUser("avatar_pending");
+        String assetId = JsonPath.read(createAvatarUpload(user), "$.data.assetId");
+
+        mockMvc.perform(patch("/api/v1/me")
+                        .header("Authorization", bearer(user))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"avatarAssetId\":\"%s\"}".formatted(assetId)))
+                .andExpect(status().isUnprocessableEntity())
+                .andExpect(jsonPath("$.code").value(42203));
+    }
+
+    /** purpose 白名单：M3.5 之后 pet_avatar 同样可申请（宠物侧引用方在 pet 服务）。 */
+    @Test
+    void petAvatarPurposeIsAlsoWhitelisted() throws Exception {
+        UUID user = newUser("avatar_purposes");
+        mockMvc.perform(post("/api/v1/media/uploads")
+                        .header("Authorization", bearer(user))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("""
+                                {"kind":"image","purpose":"pet_avatar",
+                                 "mimeType":"image/jpeg","byteSize":1024}
+                                """))
+                .andExpect(status().isCreated())
+                .andExpect(jsonPath("$.code").value(0));
+        // 白名单外的用途仍是 400/40000
+        mockMvc.perform(post("/api/v1/media/uploads")
+                        .header("Authorization", bearer(user))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("""
+                                {"kind":"image","purpose":"avatar",
+                                 "mimeType":"image/jpeg","byteSize":1024}
+                                """))
+                .andExpect(status().isBadRequest())
+                .andExpect(jsonPath("$.code").value(40000));
+    }
+}

patbond-user/src/test/java/com/patbond/patbond/user/controller/MeEndpointTest.java

@@ -17,6 +17,7 @@ import org.springframework.test.web.servlet.MockMvc;
 import java.time.Duration;
 import java.util.UUID;
 
+import static org.hamcrest.Matchers.nullValue;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
@@ -25,8 +26,9 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
 /**
  * GET /api/v1/me behind BearerAuthFilter: RS256 tokens are verified locally
  * against the configured public key (generated per test run — no committed
- * key material). Response shape is the frozen contract:
- * {userId, username, phone, createdAt} and nothing else.
+ * key material). Response shape is the M3.5 surface
+ * {userId, username, nickname, phone, avatarUrl, createdAt} and nothing else;
+ * the profile-write semantics live in MeProfileIntegrationTest.
  */
 @SpringBootTest
 @AutoConfigureMockMvc
@@ -65,9 +67,14 @@ class MeEndpointTest {
                 .andExpect(jsonPath("$.data.username").value("me_happy"))
                 .andExpect(jsonPath("$.data.phone").value("+8613800000401"))
                 .andExpect(jsonPath("$.data.createdAt").isNotEmpty())
-                // Frozen contract: no other identity fields leak out.
+                // 注册不收昵称（ADR-022 决策 D3.5-5），且 /me 不做 username 回退：
+                // 本人编辑态必须如实反映「我还没设过昵称」。
+                .andExpect(jsonPath("$.data.nickname").value(nullValue()))
+                .andExpect(jsonPath("$.data.avatarUrl").value(nullValue()))
+                // No other identity field leaks out.
                 .andExpect(jsonPath("$.data.id").doesNotExist())
-                .andExpect(jsonPath("$.data.nickname").doesNotExist());
+                .andExpect(jsonPath("$.data.avatarAssetId").doesNotExist())
+                .andExpect(jsonPath("$.data.bio").doesNotExist());
     }
 
     @Test

patbond-user/src/test/java/com/patbond/patbond/user/controller/MeProfileIntegrationTest.java

@@ -0,0 +1,430 @@
+package com.patbond.patbond.user.controller;
+
+import com.jayway.jsonpath.JsonPath;
+import com.patbond.patbond.user.TestcontainersConfiguration;
+import com.patbond.patbond.user.security.InternalAuthFilter;
+import com.patbond.patbond.user.support.TestJwtKeys;
+import com.patbond.patbond.user.support.UuidV7;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Import;
+import org.springframework.http.MediaType;
+import org.springframework.jdbc.core.simple.JdbcClient;
+import org.springframework.test.context.DynamicPropertyRegistry;
+import org.springframework.test.context.DynamicPropertySource;
+import org.springframework.test.web.servlet.MockMvc;
+
+import java.time.Duration;
+import java.time.OffsetDateTime;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.hamcrest.Matchers.nullValue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.patch;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+/**
+ * T3.5-04 用户资料读写：GET/PATCH /api/v1/me 的六类路径（成功 / 参数错 /
+ * 不存在 / 无权限 / 并发 / 重放）与三项专项（昵称边界值与清空、头像 asset
+ * 非法三态、/me 不回退 而 /internal 回退）。
+ *
+ * <p>本类不配置对象存储，因此断言 {@code avatarUrl} 恒为 null——这正是
+ * 「存储未配置时资料读取整体降级而不失败」的实证；真实签名 URL 的全链路
+ * （创建上传 → 直传 → complete → 挂头像 → URL 可访问）在
+ * MeAvatarSigningIntegrationTest 用真实 MinIO 覆盖。</p>
+ */
+@SpringBootTest
+@AutoConfigureMockMvc
+@Import(TestcontainersConfiguration.class)
+class MeProfileIntegrationTest {
+
+    private static final String INTERNAL_TOKEN = "test-internal-token";
+
+    /** 32 个 CJK 码点：恰好压在 ck_users_nickname 的上界上。 */
+    private static final String NICKNAME_32_CJK = "豆".repeat(32);
+
+    /**
+     * 32 个 emoji 码点（UTF-16 长度 64）：证明长度校验按码点而非 Java
+     * String.length() 计——PostgreSQL char_length 数的是码点，若按 UTF-16
+     * 长度校验，这个数据库能存的昵称会被应用层误拒。
+     */
+    private static final String NICKNAME_32_EMOJI = "🐶".repeat(32);
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private JdbcClient jdbcClient;
+
+    @DynamicPropertySource
+    static void jwtPublicKey(DynamicPropertyRegistry registry) {
+        registry.add("patbond.jwt.public-key", TestJwtKeys::publicPem);
+    }
+
+    // ---- helpers -------------------------------------------------------
+
+    private UUID newUser(String username) {
+        UUID id = UuidV7.generate();
+        jdbcClient.sql("INSERT INTO identity.users (id, username) VALUES (:id, :username)")
+                .param("id", id)
+                .param("username", username)
+                .update();
+        return id;
+    }
+
+    private static String bearer(UUID userId) {
+        return "Bearer " + TestJwtKeys.accessToken(
+                TestJwtKeys.KEY_PAIR.getPrivate(), userId, Duration.ofMinutes(15));
+    }
+
+    /** 一枚 media.assets 行，用途/状态/归属可控（模拟 T3-03 的产物）。 */
+    private UUID insertAsset(UUID ownerUserId, String purpose, String status) {
+        UUID id = UuidV7.generate();
+        jdbcClient.sql("""
+                        INSERT INTO media.assets
+                            (id, owner_user_id, kind, purpose, storage_type, bucket, object_key,
+                             mime_type, byte_size, status, ready_at, deleted_at)
+                        VALUES (:id, :owner, 'image', :purpose, 'object', 'patbond-media',
+                                :objectKey, 'image/jpeg', 2048, :status, :readyAt, :deletedAt)
+                        """)
+                .param("id", id)
+                .param("owner", ownerUserId)
+                .param("purpose", purpose)
+                .param("objectKey", purpose + "/2026/09/" + id)
+                .param("status", status)
+                .param("readyAt", "ready".equals(status) ? OffsetDateTime.now() : null)
+                // ck_media_deleted：status='deleted' 必带 deleted_at
+                .param("deletedAt", "deleted".equals(status) ? OffsetDateTime.now() : null)
+                .update();
+        return id;
+    }
+
+    private String patchMe(UUID userId, String body, int expectedStatus) throws Exception {
+        return mockMvc.perform(patch("/api/v1/me")
+                        .header("Authorization", bearer(userId))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(body))
+                .andExpect(status().is(expectedStatus))
+                .andReturn().getResponse().getContentAsString();
+    }
+
+    private void patchMeExpectingCode(UUID userId, String body, int httpStatus, int bizCode)
+            throws Exception {
+        mockMvc.perform(patch("/api/v1/me")
+                        .header("Authorization", bearer(userId))
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(body))
+                .andExpect(status().is(httpStatus))
+                .andExpect(jsonPath("$.code").value(bizCode));
+    }
+
+    private String getMe(UUID userId) throws Exception {
+        return mockMvc.perform(get("/api/v1/me").header("Authorization", bearer(userId)))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+    }
+
+    /** 他人视角的展示名（/internal 批量接口，回退在 SQL 层）。 */
+    private String publicNickname(UUID userId) throws Exception {
+        String body = mockMvc.perform(get("/internal/users/profiles")
+                        .header(InternalAuthFilter.HEADER, INTERNAL_TOKEN)
+                        .queryParam("ids", userId.toString()))
+                .andExpect(status().isOk())
+                .andReturn().getResponse().getContentAsString();
+        List<Map<String, Object>> rows = JsonPath.read(body, "$.data");
+        return (String) rows.get(0).get("nickname");
+    }
+
+    private UUID dbAvatarAssetId(UUID userId) {
+        return jdbcClient.sql("SELECT avatar_asset_id FROM identity.users WHERE id = :id")
+                .param("id", userId)
+                .query(UUID.class)
+                .optional()
+                .orElse(null);
+    }
+
+    // ---- 成功路径 -------------------------------------------------------
+
+    @Test
+    void setsNicknameAndBothSidesAgree() throws Exception {
+        UUID user = newUser("me_nick_set");
+
+        String patched = patchMe(user, "{\"nickname\":\"豆豆家长\"}", 200);
+        assertThat((String) JsonPath.read(patched, "$.data.nickname")).isEqualTo("豆豆家长");
+
+        assertThat((String) JsonPath.read(getMe(user), "$.data.nickname")).isEqualTo("豆豆家长");
+        // 双端一致：他人看到的展示名也立即是昵称（Feed 作者名同链路）
+        assertThat(publicNickname(user)).isEqualTo("豆豆家长");
+    }
+
+    @Test
+    void trimsNicknameLikeBtrim() throws Exception {
+        UUID user = newUser("me_nick_trim");
+        String patched = patchMe(user, "{\"nickname\":\"  豆豆  \"}", 200);
+        assertThat((String) JsonPath.read(patched, "$.data.nickname")).isEqualTo("豆豆");
+    }
+
+    /**
+     * /me 是本人编辑态，故 nickname 为 DB 原值（清空后为 null）；他人视角的
+     * /internal 才回退 username。这两者的差异是本单的核心语义定型。
+     */
+    @Test
+    void clearingNicknameIsNullOnMeButFallsBackForOtherPeople() throws Exception {
+        UUID user = newUser("me_nick_clear");
+        patchMe(user, "{\"nickname\":\"临时昵称\"}", 200);
+
+        String cleared = patchMe(user, "{\"nickname\":null}", 200);
+        assertThat((Object) JsonPath.read(cleared, "$.data.nickname")).isNull();
+        assertThat((Object) JsonPath.read(getMe(user), "$.data.nickname")).isNull();
+        assertThat(publicNickname(user)).isEqualTo("me_nick_clear");
+    }
+
+    @Test
+    void absentFieldIsLeftUnchanged() throws Exception {
+        UUID user = newUser("me_absent");
+        patchMe(user, "{\"nickname\":\"保持不动\"}", 200);
+
+        // 只提交 avatarAssetId=null：nickname 未出现在 body 里，必须不受影响
+        String patched = patchMe(user, "{\"avatarAssetId\":null}", 200);
+        assertThat((String) JsonPath.read(patched, "$.data.nickname")).isEqualTo("保持不动");
+    }
+
+    @Test
+    void setsAndClearsAvatar() throws Exception {
+        UUID user = newUser("me_avatar_ok");
+        UUID asset = insertAsset(user, "user_avatar", "ready");
+
+        String patched = patchMe(user, "{\"avatarAssetId\":\"%s\"}".formatted(asset), 200);
+        assertThat(dbAvatarAssetId(user)).isEqualTo(asset);
+        // 对象存储未配置 → 整体降级为 null URL，而不是 500
+        assertThat((Object) JsonPath.read(patched, "$.data.avatarUrl")).isNull();
+
+        patchMe(user, "{\"avatarAssetId\":null}", 200);
+        assertThat(dbAvatarAssetId(user)).isNull();
+    }
+
+    @Test
+    void acceptsNicknameAndAvatarInOneRequest() throws Exception {
+        UUID user = newUser("me_both");
+        UUID asset = insertAsset(user, "user_avatar", "ready");
+
+        String patched = patchMe(user,
+                "{\"nickname\":\"一次改两样\",\"avatarAssetId\":\"%s\"}".formatted(asset), 200);
+        assertThat((String) JsonPath.read(patched, "$.data.nickname")).isEqualTo("一次改两样");
+        assertThat(dbAvatarAssetId(user)).isEqualTo(asset);
+    }
+
+    // ---- 参数错路径（昵称边界值 + 畸形入参 + 空 patch） -------------------
+
+    @Test
+    void acceptsNicknameAtBothBoundaries() throws Exception {
+        UUID user = newUser("me_nick_bounds");
+
+        assertThat((String) JsonPath.read(patchMe(user, "{\"nickname\":\"豆\"}", 200),
+                "$.data.nickname")).isEqualTo("豆");
+        assertThat((String) JsonPath.read(
+                patchMe(user, "{\"nickname\":\"%s\"}".formatted(NICKNAME_32_CJK), 200),
+                "$.data.nickname")).isEqualTo(NICKNAME_32_CJK);
+        assertThat((String) JsonPath.read(
+                patchMe(user, "{\"nickname\":\"%s\"}".formatted(NICKNAME_32_EMOJI), 200),
+                "$.data.nickname")).isEqualTo(NICKNAME_32_EMOJI);
+    }
+
+    @Test
+    void rejectsNicknameOverThirtyTwoCodePoints() throws Exception {
+        UUID user = newUser("me_nick_long");
+        patchMeExpectingCode(user, "{\"nickname\":\"%s\"}".formatted("豆".repeat(33)), 400, 40000);
+        patchMeExpectingCode(user, "{\"nickname\":\"%s\"}".formatted("🐶".repeat(33)), 400, 40000);
+        // 拒绝后 DB 未被写入
+        assertThat((Object) JsonPath.read(getMe(user), "$.data.nickname")).isNull();
+    }
+
+    /**
+     * 空白昵称是参数错，不是「隐式清空」——清空只有显式 null 一种表达，
+     * 否则「用户不小心提交了空格」与「用户想删昵称」无法区分。
+     */
+    @Test
+    void rejectsWhitespaceOnlyNicknameInsteadOfClearing() throws Exception {
+        UUID user = newUser("me_nick_blank");
+        patchMe(user, "{\"nickname\":\"原昵称\"}", 200);
+
+        patchMeExpectingCode(user, "{\"nickname\":\"   \"}", 400, 40000);
+        patchMeExpectingCode(user, "{\"nickname\":\"\"}", 400, 40000);
+        assertThat((String) JsonPath.read(getMe(user), "$.data.nickname")).isEqualTo("原昵称");
+    }
+
+    @Test
+    void rejectsPatchThatTouchesNothing() throws Exception {
+        UUID user = newUser("me_empty_patch");
+        patchMeExpectingCode(user, "{}", 400, 40000);
+        // 只带未声明字段同样等于「什么都没改」
+        patchMeExpectingCode(user, "{\"unknownField\":\"x\"}", 400, 40000);
+    }
+
+    @Test
+    void rejectsMalformedBody() throws Exception {
+        UUID user = newUser("me_malformed");
+        patchMeExpectingCode(user, "{\"avatarAssetId\":\"not-a-uuid\"}", 400, 40000);
+        patchMeExpectingCode(user, "{\"nickname\":", 400, 40000);
+        patchMeExpectingCode(user, "{\"avatarAssetId\":42}", 400, 40000);
+    }
+
+    // ---- 头像 asset 非法三态（不存在/非本人/错用途/未就绪） ---------------
+
+    @Test
+    void rejectsUnknownOrForeignAvatarAssetWithMergedNotFound() throws Exception {
+        UUID user = newUser("me_asset_foreign");
+        UUID stranger = newUser("me_asset_stranger");
+        UUID strangerAsset = insertAsset(stranger, "user_avatar", "ready");
+
+        // 幽灵 id 与他人 asset 同答 40405（防枚举合并）
+        patchMeExpectingCode(user,
+                "{\"avatarAssetId\":\"%s\"}".formatted(UUID.randomUUID()), 404, 40405);
+        patchMeExpectingCode(user,
+                "{\"avatarAssetId\":\"%s\"}".formatted(strangerAsset), 404, 40405);
+        assertThat(dbAvatarAssetId(user)).isNull();
+    }
+
+    @Test
+    void rejectsAssetWithWrongPurpose() throws Exception {
+        UUID user = newUser("me_asset_purpose");
+        UUID postImage = insertAsset(user, "post_image", "ready");
+
+        patchMeExpectingCode(user, "{\"avatarAssetId\":\"%s\"}".formatted(postImage), 404, 40405);
+        assertThat(dbAvatarAssetId(user)).isNull();
+    }
+
+    @Test
+    void rejectsAvatarAssetThatIsNotReady() throws Exception {
+        UUID user = newUser("me_asset_state");
+        UUID uploading = insertAsset(user, "user_avatar", "uploading");
+        UUID failed = insertAsset(user, "user_avatar", "failed");
+        UUID deleted = insertAsset(user, "user_avatar", "deleted");
+
+        patchMeExpectingCode(user, "{\"avatarAssetId\":\"%s\"}".formatted(uploading), 422, 42203);
+        patchMeExpectingCode(user, "{\"avatarAssetId\":\"%s\"}".formatted(failed), 422, 42203);
+        // deleted 归入防枚举合并的 40405：已删资源对引用方就是不存在
+        patchMeExpectingCode(user, "{\"avatarAssetId\":\"%s\"}".formatted(deleted), 404, 40405);
+        assertThat(dbAvatarAssetId(user)).isNull();
+    }
+
+    // ---- 无权限路径 -----------------------------------------------------
+
+    @Test
+    void patchWithoutOrWithBadTokenIs40101() throws Exception {
+        mockMvc.perform(patch("/api/v1/me")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"nickname\":\"无票乘车\"}"))
+                .andExpect(status().isUnauthorized())
+                .andExpect(jsonPath("$.code").value(40101));
+        mockMvc.perform(patch("/api/v1/me")
+                        .header("Authorization", "Bearer not.a.jwt")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"nickname\":\"伪票\"}"))
+                .andExpect(status().isUnauthorized())
+                .andExpect(jsonPath("$.code").value(40101));
+    }
+
+    // ---- 不存在路径 -----------------------------------------------------
+
+    @Test
+    void softDeletedUserGetsUserNotFoundOnBothVerbs() throws Exception {
+        UUID user = newUser("me_gone");
+        jdbcClient.sql("""
+                        UPDATE identity.users
+                        SET status = 'deleted', deleted_at = now()
+                        WHERE id = :id
+                        """)
+                .param("id", user)
+                .update();
+
+        mockMvc.perform(get("/api/v1/me").header("Authorization", bearer(user)))
+                .andExpect(status().isNotFound())
+                .andExpect(jsonPath("$.code").value(40400));
+        patchMeExpectingCode(user, "{\"nickname\":\"亡者昵称\"}", 404, 40400);
+    }
+
+    // ---- 并发路径 -------------------------------------------------------
+
+    /**
+     * 两个并发 PATCH 各改一个字段：都必须留下。这是「列级选择性 UPDATE 而非
+     * 读-合并-写」的实证——若走整行合并写，后到的那个会把对方刚写的字段
+     * 悄悄还原（丢失更新）。/me 无版本号乐观锁，靠的正是这个性质。
+     */
+    @Test
+    void concurrentDisjointPatchesBothSurvive() throws Exception {
+        UUID user = newUser("me_concurrent");
+        UUID asset = insertAsset(user, "user_avatar", "ready");
+        CyclicBarrier startTogether = new CyclicBarrier(2);
+        ExecutorService pool = Executors.newFixedThreadPool(2);
+        try {
+            Callable<Integer> nicknameWriter = () -> {
+                startTogether.await();
+                return mockMvc.perform(patch("/api/v1/me")
+                                .header("Authorization", bearer(user))
+                                .contentType(MediaType.APPLICATION_JSON)
+                                .content("{\"nickname\":\"并发昵称\"}"))
+                        .andReturn().getResponse().getStatus();
+            };
+            Callable<Integer> avatarWriter = () -> {
+                startTogether.await();
+                return mockMvc.perform(patch("/api/v1/me")
+                                .header("Authorization", bearer(user))
+                                .contentType(MediaType.APPLICATION_JSON)
+                                .content("{\"avatarAssetId\":\"%s\"}".formatted(asset)))
+                        .andReturn().getResponse().getStatus();
+            };
+            Future<Integer> first = pool.submit(nicknameWriter);
+            Future<Integer> second = pool.submit(avatarWriter);
+            assertThat(first.get()).isEqualTo(200);
+            assertThat(second.get()).isEqualTo(200);
+        } finally {
+            pool.shutdownNow();
+        }
+
+        assertThat((String) JsonPath.read(getMe(user), "$.data.nickname")).isEqualTo("并发昵称");
+        assertThat(dbAvatarAssetId(user)).isEqualTo(asset);
+    }
+
+    // ---- 重放路径 -------------------------------------------------------
+
+    /**
+     * PATCH /me 是幂等的（无版本号、无幂等键）：同一请求重放两次，第二次同样
+     * 200 且状态与首次完全一致——重复点「保存」不会产生二次副作用。
+     */
+    @Test
+    void repeatingTheSamePatchIsStable() throws Exception {
+        UUID user = newUser("me_replay");
+        UUID asset = insertAsset(user, "user_avatar", "ready");
+        String body = "{\"nickname\":\"重放昵称\",\"avatarAssetId\":\"%s\"}".formatted(asset);
+
+        String firstNickname = JsonPath.read(patchMe(user, body, 200), "$.data.nickname");
+        String secondNickname = JsonPath.read(patchMe(user, body, 200), "$.data.nickname");
+
+        assertThat(secondNickname).isEqualTo(firstNickname).isEqualTo("重放昵称");
+        assertThat(dbAvatarAssetId(user)).isEqualTo(asset);
+    }
+
+    // ---- GET 形态回归 ---------------------------------------------------
+
+    @Test
+    void meCarriesNickAndAvatarUrlFieldsAlways() throws Exception {
+        UUID user = newUser("me_shape");
+        mockMvc.perform(get("/api/v1/me").header("Authorization", bearer(user)))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.data.nickname").value(nullValue()))
+                .andExpect(jsonPath("$.data.avatarUrl").value(nullValue()))
+                .andExpect(jsonPath("$.data.username").value("me_shape"));
+    }
+}

patbond-user/src/test/java/com/patbond/patbond/user/media/MediaUploadIntegrationTest.java

@@ -241,6 +241,8 @@ class MediaUploadIntegrationTest {
     @Test
     void rejectsKindAndPurposeOutsideWhitelist() throws Exception {
         UUID user = newUser("media_bad_enum");
+        // M3.5 起 user_avatar/pet_avatar 已进白名单（ADR-022），反例改用
+        // 一个仍未开放的用途，保持本用例「白名单外必拒」的语义。
         mockMvc.perform(post("/api/v1/media/uploads")
                         .header("Authorization", bearer(user))
                         .contentType(MediaType.APPLICATION_JSON)
@@ -254,7 +256,7 @@ class MediaUploadIntegrationTest {
                         .header("Authorization", bearer(user))
                         .contentType(MediaType.APPLICATION_JSON)
                         .content("""
-                                {"kind":"image","purpose":"pet_avatar",
+                                {"kind":"image","purpose":"id_card",
                                  "mimeType":"image/jpeg","byteSize":1024}
                                 """))
                 .andExpect(status().isBadRequest())