新增：首页 Feed 接入真实数据——四态/尾部三态/聚合曝光埋点，社区 demo 消亡第一页（T3-14）

- home_page Feed segment 改接 CommunityController：骨架屏首载、空态 CTA、
  错误横幅重试、下拉刷新（失败保留旧列表 + SnackBar）、触底游标翻页
  （失败态只走显式重试，不随滚动风暴自动重打）
- PostCard 三形态（单图通栏 4:3 / 多图折叠封面 +N 角标 / 纯文字 6 行）+
  PostMediaGrid（列数规则 + ink 80% scrim 精算）+ LikeButton（error 族修订
  Colors.red，T3-14 纯展示禁用态，ToggleSync 接线留 T3-15/16）+ FeedSkeleton
  （呼吸动效尊重减弱动态设置）；降级作者统一「宠友」占位
- SignedNetworkImage：预签名 URL 缓存 key 剥离 X-Amz-* 签名参数，
  RemoteImage 全仓换用（同图不同签名命中同一缓存条目）
- feed 域埋点：feed_viewed 聚合曝光（浏览段开/结算于切 Tab、切分段、
  退后台、销毁；≥50% 可见 ≥500ms 段内按帖去重，postId 不上报）+
  feed_load_failed（refresh/load_more 双路，会话失效不报）
- integration_test/feed_live_test.dart：compose 六容器 Linux 桌面真链路
  实测入口（PATBOND_FEED_LIVE=1 门控，默认跳过）
- 测试 379 → 421（+42）：四态/尾部三态/翻页不丢不重/降级作者/曝光结算
  时机/缓存 key/事件属性全覆盖；analyze 0，format 无 diff

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

integration_test/feed_live_test.dart

@@ -0,0 +1,112 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:integration_test/integration_test.dart';
+import 'package:patbond_flutter/app/app.dart';
+import 'package:patbond_flutter/core/widgets/post_card.dart';
+import 'package:patbond_flutter/features/auth/session_manager.dart';
+
+/// 内存 token 存储（桌面实测环境无 keyring；不落任何持久化）。
+class _InMemoryTokenStore implements TokenStore {
+  final Map<String, String> _values = {};
+
+  @override
+  Future<String?> read(String key) async => _values[key];
+
+  @override
+  Future<void> write(String key, String value) async => _values[key] = value;
+
+  @override
+  Future<void> delete(String key) async => _values.remove(key);
+}
+
+/// T3-14 compose 真链路桌面实测（默认跳过，不计入常规测试套件）：
+///
+/// ```bash
+/// # 先起后端六容器（patbond-api 仓库根）并用 scratch 种子脚本发帖，再：
+/// PATBOND_FEED_LIVE=1 flutter test integration_test/feed_live_test.dart -d linux
+/// ```
+///
+/// 驱动**真实 App**（Linux 桌面渲染管线 + 真实 HTTP + MinIO 预签名图片）：
+/// 注册账号 → UI 登录 → Feed 首屏真数据 → 滚动触底游标翻页到底 →
+/// 下拉刷新。会话存储注入内存实现（桌面环境无 keyring，不动生产配置）。
+void main() {
+  final binding = IntegrationTestWidgetsFlutterBinding.ensureInitialized();
+  binding.framePolicy = LiveTestWidgetsFlutterBindingFramePolicy.fullyLive;
+
+  final enabled = Platform.environment['PATBOND_FEED_LIVE'] == '1';
+  const authBase = 'http://127.0.0.1:8081';
+
+  Future<void> pumpUntil(
+    WidgetTester tester,
+    Finder finder, {
+    Duration timeout = const Duration(seconds: 20),
+  }) async {
+    final deadline = DateTime.now().add(timeout);
+    while (DateTime.now().isBefore(deadline)) {
+      await tester.pump(const Duration(milliseconds: 250));
+      if (finder.evaluate().isNotEmpty) return;
+    }
+    fail('等待超时：$finder');
+  }
+
+  testWidgets('Feed 桌面真链路：登录 → 首屏 → 游标翻页到底 → 下拉刷新', (tester) async {
+    // ---- 注册一次性账号（随机凭据，不落持久化）----
+    final seed = DateTime.now().millisecondsSinceEpoch;
+    final username = 'feedlive$seed';
+    final password = 'Live1234!$seed';
+    final client = HttpClient();
+    final request = await client.postUrl(
+      Uri.parse('$authBase/api/v1/auth/register'),
+    );
+    request.headers.contentType = ContentType.json;
+    request.add(
+      utf8.encode(
+        jsonEncode({
+          'username': username,
+          'phone': '+86137${(seed % 100000000).toString().padLeft(8, '0')}',
+          'password': password,
+        }),
+      ),
+    );
+    final response = await request.close();
+    expect(response.statusCode, 200, reason: '注册测试账号失败');
+    client.close();
+
+    // ---- 启动真实 App（仅注入内存会话存储，其余全为生产实现）----
+    await tester.pumpWidget(
+      App(sessionManager: SessionManager(store: _InMemoryTokenStore())),
+    );
+    await pumpUntil(tester, find.text('登录'));
+
+    await tester.enterText(find.byType(TextField).at(0), username);
+    await tester.enterText(find.byType(TextField).at(1), password);
+    await tester.tap(find.text('登录'));
+
+    // ---- Feed 首屏：真实 getFeed + 卡片渲染 ----
+    await pumpUntil(tester, find.byType(PostCard));
+    expect(find.textContaining('compose 实测'), findsWidgets);
+
+    // ---- 触底翻页到「没有更多了」（26 帖 / 服务端页长 20 → 两页取齐）----
+    final list = find.byType(ListView).first;
+    for (var i = 0; i < 12; i++) {
+      await tester.fling(list, const Offset(0, -700), 1500);
+      await tester.pump(const Duration(milliseconds: 400));
+      if (find.text('没有更多了').evaluate().isNotEmpty) break;
+    }
+    await pumpUntil(tester, find.text('没有更多了'));
+    // 最早一帖（#1）在第二页尾部——游标翻页取齐的直接证据。
+    expect(find.textContaining('#1：'), findsOneWidget);
+
+    // ---- 回顶下拉刷新：整体替换后首屏仍在 ----
+    for (var i = 0; i < 12; i++) {
+      await tester.fling(list, const Offset(0, 700), 1500);
+      await tester.pump(const Duration(milliseconds: 200));
+    }
+    await tester.fling(list, const Offset(0, 400), 1000);
+    await pumpUntil(tester, find.byType(PostCard));
+    expect(find.textContaining('compose 实测'), findsWidgets);
+  }, skip: !enabled);
+}

lib/app/app.dart

@@ -14,6 +14,7 @@ import 'package:patbond_flutter/features/auth/session_manager.dart';
 import 'package:patbond_flutter/features/auth/splash_page.dart';
 import 'package:patbond_flutter/features/community/community_controller.dart';
 import 'package:patbond_flutter/features/community/community_repository.dart';
+import 'package:patbond_flutter/features/community/feed_analytics.dart';
 import 'package:patbond_flutter/features/main/main_shell_page.dart';
 import 'package:patbond_flutter/features/pets/health_record_analytics.dart';
 import 'package:patbond_flutter/features/pets/pet_analytics.dart';
@@ -48,6 +49,7 @@ class _AppState extends State<App> {
   late final CommunityController communityController;
   late final PetAnalytics petAnalytics;
   late final HealthRecordAnalytics healthRecordAnalytics;
+  late final FeedAnalytics feedAnalytics;
   late final SessionTracker _sessionTracker;
   late final AnalyticsService _analytics;
   late final PageViewTracker _pageViewTracker;
@@ -93,12 +95,13 @@ class _AppState extends State<App> {
     petsController = PetsController(
       repository: widget.petsRepository ?? _buildPetsRepository(),
     );
-    // T3-12 只装配数据层；Feed segment 的 UI 接线在 T3-14 挂入主壳。
+    // T3-14：Feed segment 接线主壳（数据层 T3-12 就位）。
     communityController = CommunityController(
       repository: widget.communityRepository ?? _buildCommunityRepository(),
     );
     petAnalytics = PetAnalytics(_analytics.trackEvent);
     healthRecordAnalytics = HealthRecordAnalytics(_analytics.trackEvent);
+    feedAnalytics = FeedAnalytics(_analytics.trackEvent);
 
     // 认证状态切换补点（根路由 AnimatedSwitcher 无路由事件）
     sessionManager.addListener(_reportAuthStateChange);
@@ -231,8 +234,10 @@ class _AppState extends State<App> {
           key: const ValueKey('shell'),
           appState: appState,
           petsController: petsController,
+          communityController: communityController,
           petAnalytics: petAnalytics,
           healthRecordAnalytics: healthRecordAnalytics,
+          feedAnalytics: feedAnalytics,
           pageViewTracker: _pageViewTracker,
           onLogout: authRepository.logout,
         );

lib/core/network/signed_network_image.dart

@@ -0,0 +1,67 @@
+import 'package:flutter/foundation.dart';
+import 'package:flutter/painting.dart';
+
+/// 预签名 URL 的图片内存缓存 key：剥离 SigV4 签名参数（`X-Amz-*`，
+/// 大小写不敏感），保留其余 query。
+///
+/// 媒体 URL 每次响应现签（TTL 1 小时），同一对象两次响应的完整 URL
+/// 必然不同；若按完整 URL 作缓存 key，同图会反复未命中、重复下载。
+/// 对象路径唯一标识 MinIO 对象，剥签名后即稳定 key。
+String presignedImageCacheKey(String url) {
+  final uri = Uri.tryParse(url);
+  if (uri == null || uri.queryParameters.isEmpty) return url;
+  final kept = <String, String>{};
+  var stripped = false;
+  uri.queryParameters.forEach((key, value) {
+    if (key.toLowerCase().startsWith('x-amz-')) {
+      stripped = true;
+    } else {
+      kept[key] = value;
+    }
+  });
+  if (!stripped) return url;
+  // Uri.replace 的 null 语义是「保留原值」，全剥空时手工截断 query。
+  if (kept.isEmpty) return url.substring(0, url.indexOf('?'));
+  return uri.replace(queryParameters: kept).toString();
+}
+
+/// 以剥签名 key 判等的网络图 provider：同对象的不同签名 URL 命中同一
+/// [ImageCache] 条目；未命中时仍以完整签名 URL 发起请求（委托
+/// [NetworkImage] 加载，其为 factory-only 接口，无法直接继承）。
+class SignedNetworkImage extends ImageProvider<SignedNetworkImage> {
+  SignedNetworkImage(this.url, {this.scale = 1.0})
+    : cacheKey = presignedImageCacheKey(url);
+
+  final String url;
+  final double scale;
+
+  /// 剥离签名参数后的稳定缓存 key。
+  final String cacheKey;
+
+  @override
+  Future<SignedNetworkImage> obtainKey(ImageConfiguration configuration) =>
+      SynchronousFuture<SignedNetworkImage>(this);
+
+  @override
+  ImageStreamCompleter loadImage(
+    SignedNetworkImage key,
+    ImageDecoderCallback decode,
+  ) {
+    final delegate = NetworkImage(key.url, scale: key.scale);
+    return delegate.loadImage(delegate, decode);
+  }
+
+  @override
+  bool operator ==(Object other) {
+    if (other.runtimeType != runtimeType) return false;
+    return other is SignedNetworkImage &&
+        other.cacheKey == cacheKey &&
+        other.scale == scale;
+  }
+
+  @override
+  int get hashCode => Object.hash(cacheKey, scale);
+
+  @override
+  String toString() => 'SignedNetworkImage("$url", cacheKey: "$cacheKey")';
+}

lib/core/widgets/feed_skeleton.dart

@@ -0,0 +1,125 @@
+import 'package:flutter/material.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+
+/// Feed 骨架屏单元（05 号规范 §3.7）：模拟单图卡——头部行（32 圆 +
+/// 两条横条）→ 4:3 通栏块 → 两条正文横条。块色 `surfaceTint`
+/// （1.18:1，装饰性占位不受对比度约束）。
+///
+/// 动效：整体不透明度 0.6 ↔ 1.0 呼吸循环 1200ms；系统「减弱动态效果」
+/// 开启时静止在 1.0。首载用法为连排 3 张（P1/P4）。
+class FeedSkeleton extends StatefulWidget {
+  const FeedSkeleton({super.key});
+
+  @override
+  State<FeedSkeleton> createState() => _FeedSkeletonState();
+}
+
+class _FeedSkeletonState extends State<FeedSkeleton>
+    with SingleTickerProviderStateMixin {
+  late final AnimationController _controller;
+
+  @override
+  void initState() {
+    super.initState();
+    _controller = AnimationController(
+      vsync: this,
+      duration: const Duration(milliseconds: 1200),
+      lowerBound: 0.6,
+      value: 1,
+    );
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final reduceMotion = MediaQuery.of(context).disableAnimations;
+    if (reduceMotion) {
+      _controller.stop();
+      _controller.value = 1;
+    } else if (!_controller.isAnimating) {
+      _controller.repeat(reverse: true);
+    }
+    return FadeTransition(
+      opacity: _controller,
+      child: Card(
+        clipBehavior: Clip.antiAlias,
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Padding(
+              padding: const EdgeInsets.all(14),
+              child: Row(
+                children: [
+                  const _SkeletonBlock(width: 32, height: 32, circle: true),
+                  const SizedBox(width: 10),
+                  Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      _SkeletonBlock(
+                        width: _relative(context, 0.40),
+                        height: 12,
+                      ),
+                      const SizedBox(height: 6),
+                      _SkeletonBlock(
+                        width: _relative(context, 0.24),
+                        height: 8,
+                      ),
+                    ],
+                  ),
+                ],
+              ),
+            ),
+            const AspectRatio(
+              aspectRatio: 4 / 3,
+              child: ColoredBox(color: AppColors.surfaceTint),
+            ),
+            Padding(
+              padding: const EdgeInsets.all(14),
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  _SkeletonBlock(width: _relative(context, 0.90), height: 12),
+                  const SizedBox(height: 8),
+                  _SkeletonBlock(width: _relative(context, 0.60), height: 12),
+                ],
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  /// 横条宽度按屏宽比例取（规范 40%/24%/90%/60%），免依赖父约束测量。
+  double _relative(BuildContext context, double fraction) =>
+      MediaQuery.of(context).size.width * fraction;
+}
+
+class _SkeletonBlock extends StatelessWidget {
+  const _SkeletonBlock({
+    required this.width,
+    required this.height,
+    this.circle = false,
+  });
+
+  final double width;
+  final double height;
+  final bool circle;
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      width: width,
+      height: height,
+      decoration: BoxDecoration(
+        color: AppColors.surfaceTint,
+        borderRadius: BorderRadius.circular(circle ? width / 2 : 6),
+      ),
+    );
+  }
+}

lib/core/widgets/like_button.dart

@@ -0,0 +1,93 @@
+import 'package:flutter/material.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+
+/// 点赞 / 收藏按钮语义变体（05 号规范 §3.5：同一组件，图标与语义色
+/// 参数化）。点赞激活 = `error` 图标 + `errorDark` 计数（demo 的
+/// `Colors.red` 3.13:1 修订弃用，D6）；收藏激活 = `accentDark` 同色。
+enum LikeButtonVariant {
+  like(
+    inactiveIcon: Icons.favorite_border,
+    activeIcon: Icons.favorite,
+    activeIconColor: AppColors.error,
+    activeCountColor: AppColors.errorDark,
+  ),
+  bookmark(
+    inactiveIcon: Icons.bookmark_border,
+    activeIcon: Icons.bookmark,
+    activeIconColor: AppColors.accentDark,
+    activeCountColor: AppColors.accentDark,
+  );
+
+  const LikeButtonVariant({
+    required this.inactiveIcon,
+    required this.activeIcon,
+    required this.activeIconColor,
+    required this.activeCountColor,
+  });
+
+  final IconData inactiveIcon;
+  final IconData activeIcon;
+  final Color activeIconColor;
+  final Color activeCountColor;
+}
+
+/// 点赞/收藏交互钮（05 号规范 §3.5 静态规格）：图标 20 + 计数 13/w600，
+/// 未激活一律 `inkSoft`（6.59:1）。触控 44×44 由 padding 撑足。
+///
+/// T3-14 只做展示（[onPressed] 传 null 即禁用态，仍按正常色渲染计数与
+/// 状态）；乐观更新动画与 ToggleSync 接线属 T3-15/16。
+class LikeButton extends StatelessWidget {
+  const LikeButton({
+    required this.variant,
+    required this.active,
+    required this.count,
+    super.key,
+    this.onPressed,
+    this.semanticLabel,
+  });
+
+  final LikeButtonVariant variant;
+  final bool active;
+  final int count;
+  final VoidCallback? onPressed;
+  final String? semanticLabel;
+
+  @override
+  Widget build(BuildContext context) {
+    final iconColor = active ? variant.activeIconColor : AppColors.inkSoft;
+    final countColor = active ? variant.activeCountColor : AppColors.inkSoft;
+    return Semantics(
+      label: semanticLabel,
+      button: onPressed != null,
+      child: InkWell(
+        onTap: onPressed,
+        borderRadius: BorderRadius.circular(AppRadius.pill),
+        child: ConstrainedBox(
+          constraints: const BoxConstraints(minWidth: 44, minHeight: 44),
+          child: Padding(
+            padding: const EdgeInsets.symmetric(horizontal: 8),
+            child: Row(
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                Icon(
+                  active ? variant.activeIcon : variant.inactiveIcon,
+                  size: 20,
+                  color: iconColor,
+                ),
+                const SizedBox(width: 4),
+                Text(
+                  '$count',
+                  style: TextStyle(
+                    color: countColor,
+                    fontSize: 13,
+                    fontWeight: FontWeight.w600,
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/core/widgets/post_card.dart

@@ -0,0 +1,240 @@
+import 'package:flutter/material.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/core/widgets/like_button.dart';
+import 'package:patbond_flutter/core/widgets/pet_avatar.dart';
+import 'package:patbond_flutter/core/widgets/post_media_grid.dart';
+import 'package:patbond_flutter/features/community/community_display.dart';
+import 'package:patbond_flutter/features/community/community_models.dart';
+import 'package:patbond_flutter/widgets/common.dart';
+
+/// 帖子卡三形态（05 号规范 §2.1/§3.1）：home 私有 `_PostCard` 的升级
+/// 迁移，按媒体形态分支——
+///
+/// | 形态 | 媒体区 |
+/// | --- | --- |
+/// | 单图（mediaCount ≤ 1 且有封面） | 通栏出血 4:3 |
+/// | 多图（mediaCount > 1） | [PostMediaGrid] 折叠封面（FeedCard 契约只带封面 + 计数），水平 padding 14 |
+/// | 纯文字（无封面） | 无媒体区，正文放宽 ≤6 行、15/1.6 |
+///
+/// 头部行：作者头像 32 + 名字 14/w700 + 时间 12 `inkSoft`；求助帖
+/// 元信息尾追加 `TagPill(accent)`。降级作者（[AuthorSummary.isDegraded]）
+/// 渲染占位头像 + 「宠友」。操作行：[LikeButton]（点赞 / 收藏）+ 评论
+/// 计数 + 分享，各钮触控 44；互动回调传 null 即纯展示（T3-14 形态，
+/// ToggleSync 接线属 T3-15/16）。
+class PostCard extends StatelessWidget {
+  const PostCard({
+    required this.card,
+    super.key,
+    this.onTap,
+    this.onLikeTap,
+    this.onCommentTap,
+    this.onBookmarkTap,
+    this.onShareTap,
+    this.now,
+  });
+
+  final FeedCard card;
+
+  /// 整卡点按（帖子详情入口）。
+  final VoidCallback? onTap;
+
+  final VoidCallback? onLikeTap;
+  final VoidCallback? onCommentTap;
+  final VoidCallback? onBookmarkTap;
+  final VoidCallback? onShareTap;
+
+  /// 相对时间的参考时钟（测试注入；缺省取当前时间）。
+  final DateTime? now;
+
+  bool get _isTextOnly => card.coverImage == null;
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      clipBehavior: Clip.antiAlias,
+      child: InkWell(
+        onTap: onTap,
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            _header(context),
+            if (card.coverImage != null)
+              card.mediaCount > 1
+                  ? Padding(
+                      padding: const EdgeInsets.symmetric(horizontal: 14),
+                      child: PostMediaGrid(
+                        urls: [card.coverImage!.url],
+                        totalCount: card.mediaCount,
+                      ),
+                    )
+                  : AspectRatio(
+                      aspectRatio: 4 / 3,
+                      child: RemoteImage(url: card.coverImage!.url),
+                    ),
+            _body(context),
+            _actionRow(),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _header(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.all(14),
+      child: Row(
+        children: [
+          PetAvatar(size: PetAvatarSize.sm, url: card.author.avatarUrl),
+          const SizedBox(width: 10),
+          Expanded(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  authorDisplayName(card.author),
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
+                  style: const TextStyle(
+                    fontSize: 14,
+                    fontWeight: FontWeight.w700,
+                  ),
+                ),
+                const SizedBox(height: 2),
+                Row(
+                  children: [
+                    Text(
+                      feedRelativeTime(card.publishedAt, now: now),
+                      style: const TextStyle(
+                        color: AppColors.inkSoft,
+                        fontSize: 12,
+                      ),
+                    ),
+                    if (card.category == PostCategory.help) ...[
+                      const SizedBox(width: 6),
+                      const TagPill('求助', color: AppColors.accent),
+                    ],
+                  ],
+                ),
+              ],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _body(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.fromLTRB(14, 12, 14, 0),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          if (card.title != null) ...[
+            Text(
+              card.title!,
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+              style: Theme.of(context).textTheme.titleMedium,
+            ),
+            const SizedBox(height: 6),
+          ],
+          Text(
+            card.contentPreview,
+            // 纯文字帖放宽至 6 行并升字号补偿视觉重量（§2.1）。
+            maxLines: _isTextOnly ? 6 : 2,
+            overflow: TextOverflow.ellipsis,
+            style: _isTextOnly
+                ? const TextStyle(
+                    color: AppColors.ink,
+                    fontSize: 15,
+                    height: 1.6,
+                  )
+                : Theme.of(context).textTheme.bodyMedium,
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _actionRow() {
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 2),
+      child: Row(
+        children: [
+          LikeButton(
+            variant: LikeButtonVariant.like,
+            active: card.likedByMe,
+            count: card.likeCount,
+            onPressed: onLikeTap,
+            semanticLabel: '点赞',
+          ),
+          const SizedBox(width: 4),
+          _CommentCount(count: card.commentCount, onPressed: onCommentTap),
+          const SizedBox(width: 4),
+          LikeButton(
+            variant: LikeButtonVariant.bookmark,
+            active: card.bookmarkedByMe,
+            count: card.bookmarkCount,
+            onPressed: onBookmarkTap,
+            semanticLabel: '收藏',
+          ),
+          const Spacer(),
+          InkWell(
+            onTap: onShareTap,
+            borderRadius: BorderRadius.circular(AppRadius.pill),
+            child: const SizedBox(
+              width: 44,
+              height: 44,
+              child: Icon(
+                Icons.ios_share_outlined,
+                size: 20,
+                color: AppColors.inkSoft,
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+/// 评论计数钮（与 LikeButton 同视觉规格，无激活态）。
+class _CommentCount extends StatelessWidget {
+  const _CommentCount({required this.count, this.onPressed});
+
+  final int count;
+  final VoidCallback? onPressed;
+
+  @override
+  Widget build(BuildContext context) {
+    return InkWell(
+      onTap: onPressed,
+      borderRadius: BorderRadius.circular(AppRadius.pill),
+      child: ConstrainedBox(
+        constraints: const BoxConstraints(minWidth: 44, minHeight: 44),
+        child: Padding(
+          padding: const EdgeInsets.symmetric(horizontal: 8),
+          child: Row(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              const Icon(
+                Icons.chat_bubble_outline,
+                size: 20,
+                color: AppColors.inkSoft,
+              ),
+              const SizedBox(width: 4),
+              Text(
+                '$count',
+                style: const TextStyle(
+                  color: AppColors.inkSoft,
+                  fontSize: 13,
+                  fontWeight: FontWeight.w600,
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/core/widgets/post_media_grid.dart

@@ -0,0 +1,164 @@
+import 'package:flutter/material.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/widgets/common.dart';
+
+/// 图片九宫格展示态（05 号规范 §3.2）。
+///
+/// - 列数规则：2、4 图 → 2 列；3、5–9 图 → 3 列；全部 1:1 cover、
+///   格间距 4、单格圆角 `sm`(12)，`RemoteImage` 复用（loading tint 块 /
+///   失败图标兜底，缓存 key 已剥签名）。
+/// - 超出折叠：最多显 9 格，[totalCount] 超过显示数时末格叠
+///   `ink` 80% scrim + 白字「+N」20/w800（合成最亮白图 7.10:1；60% 档
+///   3.88:1 不达标弃用，§5.1 精算）。
+/// - 单图折叠形态：Feed 卡片契约只带封面 + mediaCount（FeedCard 裁剪），
+///   [urls] 单元素而 [totalCount] > 1 时渲染 4:3 单格 + 右下「+N」角标
+///   胶囊（同 80% scrim 精算）。
+///
+/// 编辑态（「＋」格 / 删除角标）随发布页工单（T3-17）扩展。
+class PostMediaGrid extends StatelessWidget {
+  const PostMediaGrid({
+    required this.urls,
+    super.key,
+    this.totalCount,
+    this.onCellTap,
+  }) : assert(urls.length > 0, 'PostMediaGrid 至少一张图');
+
+  /// 可展示的图片 URL（Feed 卡片仅封面一张；详情页全量）。
+  final List<String> urls;
+
+  /// 实际总张数（缺省 = urls.length）；大于可展示数时渲染「+N」。
+  final int? totalCount;
+
+  /// 格子点按（全屏浏览入口，T3-15 详情页接线）。
+  final ValueChanged<int>? onCellTap;
+
+  static const _maxCells = 9;
+  static const _spacing = 4.0;
+
+  int get _effectiveTotal => totalCount ?? urls.length;
+
+  /// 列数规则（§3.2）：2、4 → 2 列；其余 → 3 列（1 图不走网格）。
+  static int columnsFor(int cellCount) =>
+      (cellCount == 2 || cellCount == 4) ? 2 : 3;
+
+  @override
+  Widget build(BuildContext context) {
+    if (urls.length == 1) {
+      return _CollapsedCover(
+        url: urls.first,
+        hiddenCount: _effectiveTotal - 1,
+        onTap: onCellTap == null ? null : () => onCellTap!(0),
+      );
+    }
+
+    final cellCount = urls.length > _maxCells ? _maxCells : urls.length;
+    final overflow = _effectiveTotal - cellCount;
+    final columns = columnsFor(cellCount);
+    return GridView.builder(
+      shrinkWrap: true,
+      physics: const NeverScrollableScrollPhysics(),
+      gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
+        crossAxisCount: columns,
+        mainAxisSpacing: _spacing,
+        crossAxisSpacing: _spacing,
+      ),
+      itemCount: cellCount,
+      itemBuilder: (context, index) {
+        final isOverflowCell = overflow > 0 && index == cellCount - 1;
+        Widget cell = RemoteImage(
+          url: urls[index],
+          borderRadius: BorderRadius.circular(AppRadius.sm),
+        );
+        if (isOverflowCell) {
+          cell = Stack(
+            fit: StackFit.expand,
+            children: [
+              cell,
+              DecoratedBox(
+                decoration: BoxDecoration(
+                  color: AppColors.ink.withAlpha(204),
+                  borderRadius: BorderRadius.circular(AppRadius.sm),
+                ),
+                child: Center(
+                  child: Text(
+                    '+$overflow',
+                    style: const TextStyle(
+                      color: Colors.white,
+                      fontSize: 20,
+                      fontWeight: FontWeight.w800,
+                    ),
+                  ),
+                ),
+              ),
+            ],
+          );
+        }
+        if (onCellTap != null) {
+          cell = InkWell(
+            onTap: () => onCellTap!(index),
+            borderRadius: BorderRadius.circular(AppRadius.sm),
+            child: cell,
+          );
+        }
+        return cell;
+      },
+    );
+  }
+}
+
+/// 单图折叠形态：4:3 圆角封面 + 右下「+N」胶囊角标。
+class _CollapsedCover extends StatelessWidget {
+  const _CollapsedCover({
+    required this.url,
+    required this.hiddenCount,
+    this.onTap,
+  });
+
+  final String url;
+  final int hiddenCount;
+  final VoidCallback? onTap;
+
+  @override
+  Widget build(BuildContext context) {
+    Widget cover = AspectRatio(
+      aspectRatio: 4 / 3,
+      child: Stack(
+        fit: StackFit.expand,
+        children: [
+          RemoteImage(
+            url: url,
+            borderRadius: BorderRadius.circular(AppRadius.sm),
+          ),
+          if (hiddenCount > 0)
+            Positioned(
+              right: 8,
+              bottom: 8,
+              child: Container(
+                padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 3),
+                decoration: BoxDecoration(
+                  color: AppColors.ink.withAlpha(204),
+                  borderRadius: BorderRadius.circular(AppRadius.pill),
+                ),
+                child: Text(
+                  '+$hiddenCount',
+                  style: const TextStyle(
+                    color: Colors.white,
+                    fontSize: 12,
+                    fontWeight: FontWeight.w700,
+                  ),
+                ),
+              ),
+            ),
+        ],
+      ),
+    );
+    if (onTap != null) {
+      cover = InkWell(
+        onTap: onTap,
+        borderRadius: BorderRadius.circular(AppRadius.sm),
+        child: cover,
+      );
+    }
+    return cover;
+  }
+}

lib/features/community/community_display.dart

@@ -0,0 +1,33 @@
+import 'package:patbond_flutter/core/network/api_exception.dart';
+import 'package:patbond_flutter/features/community/community_models.dart';
+
+/// 降级作者（[AuthorSummary.isDegraded]，资料暂不可得或已注销）的
+/// 统一占位名（05 号规范：占位头像 + 默认名，客户端不做昵称回退拼装）。
+const degradedAuthorName = '宠友';
+
+/// 作者展示名：正常路径 nickname 恒非空（服务端已回退 username）；
+/// 降级形态统一 [degradedAuthorName]。
+String authorDisplayName(AuthorSummary author) =>
+    author.nickname ?? degradedAuthorName;
+
+/// Feed 卡片元信息的相对时间（正典「2 小时前」语言）。
+/// [now] 注入口供测试锁定时钟。
+String feedRelativeTime(DateTime time, {DateTime? now}) {
+  final reference = now ?? DateTime.now();
+  final difference = reference.difference(time.toLocal());
+  if (difference.inMinutes < 1) return '刚刚';
+  if (difference.inHours < 1) return '${difference.inMinutes} 分钟前';
+  if (difference.inDays < 1) return '${difference.inHours} 小时前';
+  if (difference.inDays < 7) return '${difference.inDays} 天前';
+  final local = time.toLocal();
+  if (local.year == reference.year) return '${local.month}月${local.day}日';
+  return '${local.year}年${local.month}月${local.day}日';
+}
+
+/// Feed 加载失败的用户话术（pets 域 petLoadErrorMessage 同构；
+/// 服务端原始 message 不上屏）。
+String feedLoadErrorMessage(ApiException? error) => switch (error) {
+  ApiNetworkException _ => '网络异常，请检查网络后重试',
+  ApiRateLimitException _ => '请求过于频繁，请稍后再试',
+  _ => '动态加载失败，请稍后重试',
+};

lib/features/community/feed_analytics.dart

@@ -0,0 +1,114 @@
+import 'package:patbond_flutter/analytics/page_view_tracker.dart';
+import 'package:patbond_flutter/core/network/api_exception.dart';
+
+/// feed 域埋点强类型封装（06 号规划 §1.4 字典 v3；后端白名单已随
+/// api dev@8089c06 就绪）。沿 pet_analytics 惯例：枚举编译期锁死，
+/// 业务代码禁止手拼事件名与属性；只记行为不记内容（隐私红线：postId
+/// 等内容 ID 一律不进 props，曝光去重键只存活于客户端内存）。
+
+/// feed_viewed / feed_load_failed 的 feedTab 枚举（06 §1.4）。
+/// M3 T3-14 仅接 home；topic / user_posts / favorites 随后续页面启用。
+enum FeedTab {
+  home('home'),
+  topic('topic'),
+  userPosts('user_posts'),
+  favorites('favorites');
+
+  const FeedTab(this.value);
+
+  final String value;
+}
+
+/// feed_load_failed 的 loadType 枚举。
+enum FeedLoadType {
+  refresh('refresh'),
+  loadMore('load_more');
+
+  const FeedLoadType(this.value);
+
+  final String value;
+}
+
+/// feed 加载失败原因（06 v3 失败枚举基底）。网络归并口径同 pet 域：
+/// 断网/超时/5xx 均并入 network_error，server_error 保留兜底。
+enum FeedLoadFailureReason {
+  rateLimited('rate_limited'),
+  networkError('network_error'),
+  serverError('server_error');
+
+  const FeedLoadFailureReason(this.value);
+
+  final String value;
+}
+
+/// 类型化异常 → 失败原因；会话失效返回 null（应用即将回登录页，
+/// 不作为 Feed 加载失败上报）。
+FeedLoadFailureReason? feedLoadFailureReasonOf(ApiException error) =>
+    switch (error) {
+      ApiNetworkException _ => FeedLoadFailureReason.networkError,
+      ApiRateLimitException _ => FeedLoadFailureReason.rateLimited,
+      SessionExpiredException _ => null,
+      _ => FeedLoadFailureReason.serverError,
+    };
+
+class FeedAnalytics {
+  FeedAnalytics(this._track);
+
+  /// 生产传 `AnalyticsService.trackEvent`，测试传录制桩。
+  final TrackEventFn _track;
+
+  /// 一个 Feed 浏览段的聚合曝光（06 §1.2 裁定）：离开 Feed（路由跳走 /
+  /// 退后台）时发一条，携带段内曝光卡片数（≥50% 可见 ≥500ms、按帖去重
+  /// 后的**计数**）、翻页数、刷新数与前台停留时长。
+  void feedViewed({
+    required FeedTab feedTab,
+    required int durationMs,
+    required int impressionCount,
+    required int loadMoreCount,
+    required int refreshCount,
+  }) {
+    _track('feed_viewed', {
+      'feedTab': feedTab.value,
+      'durationMs': durationMs,
+      'impressionCount': impressionCount,
+      'loadMoreCount': loadMoreCount,
+      'refreshCount': refreshCount,
+    });
+  }
+
+  /// 刷新或翻页请求失败（M3 验收「分页不丢失不重复」的客户端观测点）。
+  ///
+  /// [errorCode] 为业务错误码（网络错误时缺席）；[httpStatus] 由五位
+  /// 业务码推导（`code ~/ 100`，pet 域同款口径）。
+  void feedLoadFailed({
+    required FeedTab feedTab,
+    required FeedLoadType loadType,
+    required FeedLoadFailureReason reason,
+    int? errorCode,
+  }) {
+    _track('feed_load_failed', {
+      'feedTab': feedTab.value,
+      'loadType': loadType.value,
+      'failureReason': reason.value,
+      'errorCode': ?errorCode,
+      if (errorCode != null && errorCode >= 10000)
+        'httpStatus': errorCode ~/ 100,
+    });
+  }
+
+  /// [feedLoadFailed] 的异常直通口：会话失效不上报。
+  void feedLoadFailedFrom(
+    ApiException error, {
+    required FeedTab feedTab,
+    required FeedLoadType loadType,
+  }) {
+    final reason = feedLoadFailureReasonOf(error);
+    if (reason == null) return;
+    feedLoadFailed(
+      feedTab: feedTab,
+      loadType: loadType,
+      reason: reason,
+      errorCode: error is ApiBusinessException ? error.code : null,
+    );
+  }
+}

lib/features/community/feed_exposure.dart

@@ -0,0 +1,110 @@
+import 'dart:async';
+import 'dart:math';
+
+import 'package:patbond_flutter/features/community/feed_analytics.dart';
+
+/// 一个「Feed 浏览段」的聚合器（06 号规划 §1.2 裁定的客户端实现）。
+///
+/// 段生命周期由页面驱动：进入 Feed（Tab 激活且分段在 Feed）开段；
+/// 离开（切 Tab / 切分段 / 退后台 / 页面销毁）时 [settle] 结算并经
+/// [FeedAnalytics.feedViewed] 发**一条**聚合事件。
+///
+/// - 曝光判定：卡片可见面积 ≥ [visibleThreshold] 且持续 ≥ [dwell]，
+///   段内按 postId 去重；postId 只作内存去重键、绝不上报（隐私红线 2），
+///   段结束即弃。
+/// - durationMs 为前台时长（退后台即结算，段天然前台连续），上限
+///   截断 30 分钟防挂机污染（06 §1.4 实现注意）。
+class FeedViewSegment {
+  FeedViewSegment({DateTime Function()? now})
+    : _now = now ?? DateTime.now,
+      _settled = false {
+    _startedAt = _now();
+  }
+
+  static const visibleThreshold = 0.5;
+  static const dwell = Duration(milliseconds: 500);
+  static const maxDuration = Duration(minutes: 30);
+
+  final DateTime Function() _now;
+  late final DateTime _startedAt;
+
+  final Set<String> _impressed = <String>{};
+  final Map<String, Timer> _dwellTimers = <String, Timer>{};
+  int _loadMoreCount = 0;
+  int _refreshCount = 0;
+  bool _settled;
+
+  /// 段内曝光卡片数（已去重；仅测试与结算读取）。
+  int get impressionCount => _impressed.length;
+
+  /// 可见性回报：≥50% 起 500ms 驻留计时，跌破或滚出视口即取消；
+  /// 驻留满即记曝光（去重后不再计时）。
+  void updateVisibility(String postId, double visibleFraction) {
+    if (_settled) return;
+    if (visibleFraction >= visibleThreshold) {
+      if (_impressed.contains(postId) || _dwellTimers.containsKey(postId)) {
+        return;
+      }
+      _dwellTimers[postId] = Timer(dwell, () {
+        _dwellTimers.remove(postId);
+        _impressed.add(postId);
+      });
+    } else {
+      _dwellTimers.remove(postId)?.cancel();
+    }
+  }
+
+  /// 用户触发的下拉刷新 / 失败重试（首屏自动预取不计）。
+  void recordRefresh() {
+    if (!_settled) _refreshCount += 1;
+  }
+
+  /// 触底翻页请求（含尾部失败重试）。
+  void recordLoadMore() {
+    if (!_settled) _loadMoreCount += 1;
+  }
+
+  /// 结算：取消在途驻留计时并冻结计数；幂等（重复调用返回 null，
+  /// 保证一段恰好一条 feed_viewed）。
+  FeedViewSummary? settle() {
+    if (_settled) return null;
+    _settled = true;
+    for (final timer in _dwellTimers.values) {
+      timer.cancel();
+    }
+    _dwellTimers.clear();
+    final elapsed = _now().difference(_startedAt);
+    return FeedViewSummary(
+      durationMs: min(elapsed.inMilliseconds, maxDuration.inMilliseconds),
+      impressionCount: _impressed.length,
+      loadMoreCount: _loadMoreCount,
+      refreshCount: _refreshCount,
+    );
+  }
+}
+
+/// [FeedViewSegment.settle] 的结算结果（feed_viewed 专有属性）。
+class FeedViewSummary {
+  const FeedViewSummary({
+    required this.durationMs,
+    required this.impressionCount,
+    required this.loadMoreCount,
+    required this.refreshCount,
+  });
+
+  final int durationMs;
+  final int impressionCount;
+  final int loadMoreCount;
+  final int refreshCount;
+
+  /// 结算即上报的便捷口。
+  void report(FeedAnalytics analytics, {FeedTab feedTab = FeedTab.home}) {
+    analytics.feedViewed(
+      feedTab: feedTab,
+      durationMs: durationMs,
+      impressionCount: impressionCount,
+      loadMoreCount: loadMoreCount,
+      refreshCount: refreshCount,
+    );
+  }
+}

lib/features/home/home_page.dart

@@ -1,42 +1,253 @@
 import 'package:flutter/material.dart';
 import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/core/widgets/empty_state_illustration.dart';
+import 'package:patbond_flutter/core/widgets/feed_skeleton.dart';
+import 'package:patbond_flutter/core/widgets/inline_error_banner.dart';
+import 'package:patbond_flutter/core/widgets/post_card.dart';
 import 'package:patbond_flutter/data/demo_data.dart';
+import 'package:patbond_flutter/features/community/community_controller.dart';
+import 'package:patbond_flutter/features/community/community_display.dart';
+import 'package:patbond_flutter/features/community/community_models.dart';
+import 'package:patbond_flutter/features/community/feed_analytics.dart';
+import 'package:patbond_flutter/features/community/feed_exposure.dart';
 import 'package:patbond_flutter/models/models.dart';
 import 'package:patbond_flutter/state/app_state.dart';
 import 'package:patbond_flutter/widgets/common.dart';
 
 enum HomeSegment { feed, services }
 
+/// 首页 Tab：Feed 段自 T3-14 起消费 [CommunityController] 真实数据
+/// （四态 + 游标翻页 + 聚合曝光埋点）；天气条/问候卡/搜索/服务段与
+/// `_StoryRow` 家具保留 demo 形态（03 号评估 §1.1 判定）。
 class HomePage extends StatefulWidget {
   const HomePage({
     required this.appState,
-    required this.onOpenPost,
+    required this.communityController,
     required this.onOpenServices,
     required this.onOpenCreate,
     super.key,
+    this.feedAnalytics,
+    this.isActive = true,
   });
 
   final AppState appState;
-  final ValueChanged<PostModel> onOpenPost;
+
+  /// Feed 数据源（Tab 级单例，app.dart 装配注入）。
+  final CommunityController communityController;
+
   final ValueChanged<bool> onOpenServices;
   final VoidCallback onOpenCreate;
 
+  /// feed 域埋点（feed_viewed 聚合曝光 + feed_load_failed）。
+  final FeedAnalytics? feedAnalytics;
+
+  /// 首页 Tab 是否为当前可见 Tab（IndexedStack 各 Tab 常驻构建，
+  /// 由主壳传入以驱动浏览段开/结算）。
+  final bool isActive;
+
   @override
   State<HomePage> createState() => _HomePageState();
 }
 
-class _HomePageState extends State<HomePage> {
+class _HomePageState extends State<HomePage> with WidgetsBindingObserver {
   HomeSegment segment = HomeSegment.feed;
   String query = '';
   String sort = '综合';
 
-  List<PostModel> get filteredPosts {
+  /// 当前 Feed 浏览段（不在 Feed 面上时为 null）。
+  FeedViewSegment? _viewSegment;
+
+  /// 曝光扫描用：postId → 卡片 GlobalKey。
+  final Map<String, GlobalKey> _cardKeys = {};
+  final GlobalKey _listKey = GlobalKey();
+
+  AppLifecycleState _lastLifecycle = AppLifecycleState.resumed;
+
+  CommunityController get _feed => widget.communityController;
+
+  bool get _feedSurfaceVisible =>
+      widget.isActive && segment == HomeSegment.feed;
+
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addObserver(this);
+    // 主壳挂载即预取（pets 先例）；重登后控制器已 reset 回 initial。
+    // 首屏自动预取不计入浏览段 refreshCount（非用户动作）。
+    if (_feed.phase == FeedPhase.initial) {
+      _refreshFeed(userInitiated: false);
+    }
+    if (_feedSurfaceVisible) _startSegment();
+  }
+
+  @override
+  void didUpdateWidget(HomePage oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (oldWidget.isActive != widget.isActive) {
+      widget.isActive ? _maybeStartSegment() : _settleSegment();
+    }
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    // 退后台即结算浏览段（06 §1.2：feed_viewed 触发点之一）；只在离开
+    // resumed 的第一次变更结算（inactive/hidden/paused 级联不重复）。
+    // 回前台若仍在 Feed 面上则开新段。
+    if (state == AppLifecycleState.resumed) {
+      _lastLifecycle = state;
+      _maybeStartSegment();
+      return;
+    }
+    if (_lastLifecycle == AppLifecycleState.resumed) {
+      _settleSegment();
+    }
+    _lastLifecycle = state;
+  }
+
+  @override
+  void dispose() {
+    _settleSegment();
+    WidgetsBinding.instance.removeObserver(this);
+    super.dispose();
+  }
+
+  // ---- 浏览段开/结算 ----
+
+  void _startSegment() {
+    _viewSegment ??= FeedViewSegment();
+    _scheduleVisibilityScan();
+  }
+
+  void _maybeStartSegment() {
+    if (_feedSurfaceVisible && _lastLifecycle == AppLifecycleState.resumed) {
+      _startSegment();
+    }
+  }
+
+  void _settleSegment() {
+    final summary = _viewSegment?.settle();
+    _viewSegment = null;
+    if (summary != null && widget.feedAnalytics != null) {
+      summary.report(widget.feedAnalytics!);
+    }
+  }
+
+  void _onSegmentChanged(HomeSegment value) {
+    if (value == segment) return;
+    setState(() => segment = value);
+    value == HomeSegment.feed ? _maybeStartSegment() : _settleSegment();
+  }
+
+  // ---- 曝光可见性扫描 ----
+
+  bool _scanScheduled = false;
+
+  /// 帧末扫描（滚动通知发生在本帧布局前，同步读 RenderBox 是旧位置；
+  /// 统一调度到 post-frame，一帧至多一次）。
+  void _scheduleVisibilityScan() {
+    if (_scanScheduled) return;
+    _scanScheduled = true;
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      _scanScheduled = false;
+      _scanVisibility();
+    });
+  }
+
+  /// 以列表视口与各卡片 RenderBox 的纵向交叠比例回报可见性
+  /// （≥50% 且驻留 ≥500ms 才计曝光，判定在 [FeedViewSegment] 内）。
+  void _scanVisibility() {
+    final viewSegment = _viewSegment;
+    if (viewSegment == null || !mounted) return;
+    final listBox = _listKey.currentContext?.findRenderObject() as RenderBox?;
+    if (listBox == null || !listBox.attached) return;
+    final viewportTop = listBox.localToGlobal(Offset.zero).dy;
+    final viewportBottom = viewportTop + listBox.size.height;
+    for (final entry in _cardKeys.entries) {
+      final box = entry.value.currentContext?.findRenderObject() as RenderBox?;
+      var fraction = 0.0;
+      if (box != null && box.attached && box.hasSize && box.size.height > 0) {
+        final top = box.localToGlobal(Offset.zero).dy;
+        final bottom = top + box.size.height;
+        final visible =
+            bottom.clamp(viewportTop, viewportBottom) -
+            top.clamp(viewportTop, viewportBottom);
+        fraction = visible / box.size.height;
+      }
+      viewSegment.updateVisibility(entry.key, fraction);
+    }
+  }
+
+  bool _onScrollNotification(ScrollNotification notification) {
+    if (segment != HomeSegment.feed) return false;
+    if (notification is ScrollUpdateNotification ||
+        notification is ScrollEndNotification) {
+      _scheduleVisibilityScan();
+      // 滚动近底触发翻页（余量 400 提前预取）；失败态不自动重试，
+      // 只走尾部重试条显式点按（避免滚动风暴反复打失败端点）。
+      if (notification.metrics.extentAfter < 400 &&
+          _feed.loadMorePhase == LoadMorePhase.idle) {
+        _loadMoreFeed();
+      }
+    }
+    return false;
+  }
+
+  // ---- 数据加载与失败埋点 ----
+
+  Future<void> _refreshFeed({required bool userInitiated}) async {
+    if (userInitiated) _viewSegment?.recordRefresh();
+    await _feed.refresh();
+    final error = _feed.refreshError ?? _feed.lastError;
+    if (error != null) {
+      widget.feedAnalytics?.feedLoadFailedFrom(
+        error,
+        feedTab: FeedTab.home,
+        loadType: FeedLoadType.refresh,
+      );
+    }
+    // 刷新失败但旧列表被保留：SnackBar 轻提示（首屏失败走 error 态横幅）。
+    if (_feed.refreshError != null && mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(feedLoadErrorMessage(_feed.refreshError))),
+      );
+    }
+  }
+
+  Future<void> _loadMoreFeed() async {
+    if (_feed.phase != FeedPhase.ready ||
+        !_feed.hasMore ||
+        _feed.loadMorePhase == LoadMorePhase.loading) {
+      return;
+    }
+    _viewSegment?.recordLoadMore();
+    await _feed.loadMore();
+    final error = _feed.loadMoreError;
+    if (error != null) {
+      widget.feedAnalytics?.feedLoadFailedFrom(
+        error,
+        feedTab: FeedTab.home,
+        loadType: FeedLoadType.loadMore,
+      );
+    }
+  }
+
+  /// T3-14 取舍：详情页数据层重写属 T3-15，demo 详情页无法按服务端
+  /// postId 渲染真实帖，故整卡点按先提示、互动按钮为纯展示禁用态。
+  void _showDetailPending() {
+    ScaffoldMessenger.of(context)
+      ..hideCurrentSnackBar()
+      ..showSnackBar(const SnackBar(content: Text('帖子详情正在接入真实数据，敬请期待')));
+  }
+
+  /// 搜索词过滤（demo 交互保留：只过滤已加载的多页缓存，不发检索请求；
+  /// 契约 v1.3.0 无搜索端点）。
+  List<FeedCard> get _visibleCards {
     final keyword = query.trim().toLowerCase();
-    if (keyword.isEmpty) return widget.appState.posts;
-    return widget.appState.posts.where((post) {
-      return post.content.toLowerCase().contains(keyword) ||
-          post.authorName.toLowerCase().contains(keyword) ||
-          post.tags.any((tag) => tag.toLowerCase().contains(keyword));
+    if (keyword.isEmpty) return _feed.feed;
+    return _feed.feed.where((card) {
+      return card.contentPreview.toLowerCase().contains(keyword) ||
+          (card.title?.toLowerCase().contains(keyword) ?? false) ||
+          authorDisplayName(card.author).toLowerCase().contains(keyword);
     }).toList();
   }
 
@@ -95,114 +306,232 @@ class _HomePageState extends State<HomePage> {
 
   @override
   Widget build(BuildContext context) {
-    return RefreshIndicator(
-      onRefresh: () async =>
-          Future<void>.delayed(const Duration(milliseconds: 500)),
-      child: ListView(
-        padding: const EdgeInsets.fromLTRB(16, 12, 16, 28),
-        children: [
-          _WeatherStatusBar(
-            weather: widget.appState.locationWeather,
-            onAreaTap: selectArea,
-            onWeatherTap: showWeatherDetails,
-          ),
-          const SizedBox(height: 12),
-          _PetGreetingCard(
-            greeting: greeting,
-            petName: widget.appState.pet.name,
-            petAvatar: widget.appState.pet.avatarUrl,
-            advice: widget.appState.locationWeather.petAdvice,
-          ),
-          const SizedBox(height: 14),
-          TextField(
-            onChanged: (value) => setState(() => query = value),
-            decoration: const InputDecoration(
-              hintText: '搜索动态、医院、美容或遛狗服务…',
-              prefixIcon: Icon(Icons.search),
-            ),
-          ),
-          const SizedBox(height: 14),
-          SegmentedButton<HomeSegment>(
-            segments: const [
-              ButtonSegment(
-                value: HomeSegment.feed,
-                icon: Icon(Icons.forum_outlined),
-                label: Text('社区动态'),
-              ),
-              ButtonSegment(
-                value: HomeSegment.services,
-                icon: Icon(Icons.storefront_outlined),
-                label: Text('本地服务'),
-              ),
-            ],
-            selected: {segment},
-            showSelectedIcon: false,
-            onSelectionChanged: (value) {
-              setState(() => segment = value.first);
-            },
-          ),
-          const SizedBox(height: 18),
-          if (segment == HomeSegment.feed) ...[
-            _StoryRow(onCreate: widget.onOpenCreate),
-            const SizedBox(height: 18),
-            _PromoCard(onTap: () => widget.onOpenServices(true)),
-            const SizedBox(height: 18),
-            if (filteredPosts.isEmpty)
-              const EmptyState(message: '没有找到相关动态')
-            else
-              ...filteredPosts.map(
-                (post) => Padding(
-                  padding: const EdgeInsets.only(bottom: 16),
-                  child: _PostCard(
-                    post: post,
-                    onTap: () => widget.onOpenPost(post),
-                    onLike: () => widget.appState.updatePost(
-                      post.copyWith(
-                        hasLiked: !post.hasLiked,
-                        likes: post.hasLiked ? post.likes - 1 : post.likes + 1,
+    return ListenableBuilder(
+      listenable: _feed,
+      builder: (context, _) {
+        // ready 后（含翻页追加）补一次可见性扫描：无滚动也能记首屏曝光。
+        if (_viewSegment != null && _feed.phase == FeedPhase.ready) {
+          _scheduleVisibilityScan();
+        }
+        return NotificationListener<ScrollNotification>(
+          onNotification: _onScrollNotification,
+          child: RefreshIndicator(
+            onRefresh: () => segment == HomeSegment.feed
+                ? _refreshFeed(userInitiated: true)
+                : Future<void>.delayed(const Duration(milliseconds: 500)),
+            child: ListView(
+              key: _listKey,
+              padding: const EdgeInsets.fromLTRB(16, 12, 16, 28),
+              children: [
+                _WeatherStatusBar(
+                  weather: widget.appState.locationWeather,
+                  onAreaTap: selectArea,
+                  onWeatherTap: showWeatherDetails,
+                ),
+                const SizedBox(height: 12),
+                _PetGreetingCard(
+                  greeting: greeting,
+                  petName: widget.appState.pet.name,
+                  petAvatar: widget.appState.pet.avatarUrl,
+                  advice: widget.appState.locationWeather.petAdvice,
+                ),
+                const SizedBox(height: 14),
+                TextField(
+                  onChanged: (value) => setState(() => query = value),
+                  decoration: const InputDecoration(
+                    hintText: '搜索动态、医院、美容或遛狗服务…',
+                    prefixIcon: Icon(Icons.search),
+                  ),
+                ),
+                const SizedBox(height: 14),
+                SegmentedButton<HomeSegment>(
+                  segments: const [
+                    ButtonSegment(
+                      value: HomeSegment.feed,
+                      icon: Icon(Icons.forum_outlined),
+                      label: Text('社区动态'),
+                    ),
+                    ButtonSegment(
+                      value: HomeSegment.services,
+                      icon: Icon(Icons.storefront_outlined),
+                      label: Text('本地服务'),
+                    ),
+                  ],
+                  selected: {segment},
+                  showSelectedIcon: false,
+                  onSelectionChanged: (value) => _onSegmentChanged(value.first),
+                ),
+                const SizedBox(height: 18),
+                if (segment == HomeSegment.feed) ...[
+                  _StoryRow(onCreate: widget.onOpenCreate),
+                  const SizedBox(height: 18),
+                  _PromoCard(onTap: () => widget.onOpenServices(true)),
+                  const SizedBox(height: 18),
+                  ..._feedSection(),
+                ] else ...[
+                  _CategoryGrid(onTap: (_) => widget.onOpenServices(false)),
+                  const SizedBox(height: 18),
+                  Row(
+                    children: [
+                      Text(
+                        '附近推荐',
+                        style: Theme.of(context).textTheme.titleLarge,
+                      ),
+                      const Spacer(),
+                      for (final item in ['综合', '距离', '评分'])
+                        Padding(
+                          padding: const EdgeInsets.only(left: 6),
+                          child: ChoiceChip(
+                            label: Text(item),
+                            selected: sort == item,
+                            onSelected: (_) => setState(() => sort = item),
+                          ),
+                        ),
+                    ],
+                  ),
+                  const SizedBox(height: 12),
+                  if (filteredProviders.isEmpty)
+                    const EmptyState(message: '没有找到相关服务')
+                  else
+                    ...filteredProviders.map(
+                      (provider) => Padding(
+                        padding: const EdgeInsets.only(bottom: 12),
+                        child: _ProviderCompactCard(
+                          provider: provider,
+                          onTap: () => widget.onOpenServices(
+                            provider.kind == ProviderKind.personal,
+                          ),
+                        ),
                       ),
                     ),
-                  ),
-                ),
-              ),
-          ] else ...[
-            _CategoryGrid(onTap: (_) => widget.onOpenServices(false)),
-            const SizedBox(height: 18),
-            Row(
-              children: [
-                Text('附近推荐', style: Theme.of(context).textTheme.titleLarge),
-                const Spacer(),
-                for (final item in ['综合', '距离', '评分'])
-                  Padding(
-                    padding: const EdgeInsets.only(left: 6),
-                    child: ChoiceChip(
-                      label: Text(item),
-                      selected: sort == item,
-                      onSelected: (_) => setState(() => sort = item),
-                    ),
-                  ),
+                ],
               ],
             ),
-            const SizedBox(height: 12),
-            if (filteredProviders.isEmpty)
-              const EmptyState(message: '没有找到相关服务')
-            else
-              ...filteredProviders.map(
-                (provider) => Padding(
-                  padding: const EdgeInsets.only(bottom: 12),
-                  child: _ProviderCompactCard(
-                    provider: provider,
-                    onTap: () => widget.onOpenServices(
-                      provider.kind == ProviderKind.personal,
-                    ),
-                  ),
-                ),
-              ),
-          ],
-        ],
-      ),
+          ),
+        );
+      },
     );
   }
+
+  // ---- Feed 段四态渲染 ----
+
+  List<Widget> _feedSection() {
+    switch (_feed.phase) {
+      case FeedPhase.initial:
+      case FeedPhase.loading:
+        return const [
+          FeedSkeleton(),
+          SizedBox(height: 16),
+          FeedSkeleton(),
+          SizedBox(height: 16),
+          FeedSkeleton(),
+        ];
+      case FeedPhase.error:
+        return [
+          Padding(
+            padding: const EdgeInsets.symmetric(vertical: 24),
+            child: Column(
+              children: [
+                InlineErrorBanner(
+                  message: feedLoadErrorMessage(_feed.lastError),
+                ),
+                const SizedBox(height: 16),
+                FilledButton(
+                  onPressed: () => _refreshFeed(userInitiated: true),
+                  child: const Text('重试'),
+                ),
+              ],
+            ),
+          ),
+        ];
+      case FeedPhase.ready:
+        if (_feed.feed.isEmpty) {
+          return [
+            EmptyStateIllustration(
+              icon: Icons.forum_outlined,
+              title: '还没有动态',
+              description: '关注的毛孩子们还没发帖，去逛逛话题吧',
+              ctaLabel: '发布第一条',
+              onCtaPressed: widget.onOpenCreate,
+            ),
+          ];
+        }
+        final cards = _visibleCards;
+        _pruneCardKeys(cards);
+        if (cards.isEmpty) {
+          return const [EmptyState(message: '没有找到相关动态')];
+        }
+        return [
+          for (final card in cards)
+            Padding(
+              padding: const EdgeInsets.only(bottom: 16),
+              child: KeyedSubtree(
+                key: _cardKeys.putIfAbsent(card.id, GlobalKey.new),
+                child: PostCard(card: card, onTap: _showDetailPending),
+              ),
+            ),
+          // 搜索过滤中不渲染尾部（过滤只作用于已加载页，翻页语义混淆）。
+          if (query.trim().isEmpty) _feedTail(),
+        ];
+    }
+  }
+
+  /// 卡片 key 表随当前列表收敛（刷新整体替换后旧帖的驻留计时作废）。
+  void _pruneCardKeys(List<FeedCard> cards) {
+    final alive = {for (final card in cards) card.id};
+    _cardKeys.removeWhere((id, _) {
+      if (alive.contains(id)) return false;
+      _viewSegment?.updateVisibility(id, 0);
+      return true;
+    });
+  }
+
+  /// 尾部三态：加载中转圈 / 失败重试 / 到底「没有更多了」。
+  Widget _feedTail() {
+    switch (_feed.loadMorePhase) {
+      case LoadMorePhase.loading:
+        return const Padding(
+          padding: EdgeInsets.symmetric(vertical: 16),
+          child: Center(
+            child: SizedBox(
+              width: 24,
+              height: 24,
+              child: CircularProgressIndicator(
+                strokeWidth: 2.5,
+                color: AppColors.primary,
+              ),
+            ),
+          ),
+        );
+      case LoadMorePhase.error:
+        return Padding(
+          padding: const EdgeInsets.symmetric(vertical: 8),
+          child: Column(
+            children: [
+              Text(
+                feedLoadErrorMessage(_feed.loadMoreError),
+                style: const TextStyle(color: AppColors.inkSoft, fontSize: 12),
+              ),
+              TextButton(
+                onPressed: _loadMoreFeed,
+                child: const Text('加载失败，点此重试'),
+              ),
+            ],
+          ),
+        );
+      case LoadMorePhase.idle:
+        if (_feed.hasMore) return const SizedBox(height: 24);
+        return const Padding(
+          padding: EdgeInsets.symmetric(vertical: 16),
+          child: Center(
+            child: Text(
+              '没有更多了',
+              style: TextStyle(color: AppColors.inkSoft, fontSize: 12),
+            ),
+          ),
+        );
+    }
+  }
 }
 
 class _WeatherStatusBar extends StatelessWidget {
@@ -661,103 +990,6 @@ class _PromoCard extends StatelessWidget {
   }
 }
 
-class _PostCard extends StatelessWidget {
-  const _PostCard({
-    required this.post,
-    required this.onTap,
-    required this.onLike,
-  });
-
-  final PostModel post;
-  final VoidCallback onTap;
-  final VoidCallback onLike;
-
-  @override
-  Widget build(BuildContext context) {
-    return Card(
-      clipBehavior: Clip.antiAlias,
-      child: InkWell(
-        onTap: onTap,
-        child: Column(
-          crossAxisAlignment: CrossAxisAlignment.start,
-          children: [
-            Padding(
-              padding: const EdgeInsets.all(14),
-              child: Row(
-                children: [
-                  RemoteImage(
-                    url: post.authorAvatar,
-                    width: 38,
-                    height: 38,
-                    borderRadius: BorderRadius.circular(19),
-                  ),
-                  const SizedBox(width: 10),
-                  Expanded(
-                    child: Column(
-                      crossAxisAlignment: CrossAxisAlignment.start,
-                      children: [
-                        Text(
-                          post.authorName,
-                          style: const TextStyle(fontWeight: FontWeight.w700),
-                        ),
-                        Text(
-                          '${post.time} · ${post.breedTag}',
-                          style: Theme.of(context).textTheme.bodySmall,
-                        ),
-                      ],
-                    ),
-                  ),
-                  const Icon(Icons.more_horiz, color: AppColors.muted),
-                ],
-              ),
-            ),
-            AspectRatio(
-              aspectRatio: 4 / 3,
-              child: RemoteImage(url: post.mainImage),
-            ),
-            Padding(
-              padding: const EdgeInsets.all(16),
-              child: Column(
-                crossAxisAlignment: CrossAxisAlignment.start,
-                children: [
-                  Text(
-                    post.content,
-                    maxLines: 2,
-                    overflow: TextOverflow.ellipsis,
-                  ),
-                  const SizedBox(height: 12),
-                  Row(
-                    children: [
-                      ActionChip(
-                        avatar: Icon(
-                          post.hasLiked
-                              ? Icons.favorite
-                              : Icons.favorite_border,
-                          size: 17,
-                          color: post.hasLiked ? Colors.red : AppColors.primary,
-                        ),
-                        label: Text('${post.likes}'),
-                        onPressed: onLike,
-                      ),
-                      const SizedBox(width: 8),
-                      Chip(
-                        avatar: const Icon(Icons.chat_bubble_outline, size: 16),
-                        label: Text('${post.comments.length}'),
-                      ),
-                      const Spacer(),
-                      const Icon(Icons.share_outlined, color: AppColors.muted),
-                    ],
-                  ),
-                ],
-              ),
-            ),
-          ],
-        ),
-      ),
-    );
-  }
-}
-
 class _CategoryGrid extends StatelessWidget {
   const _CategoryGrid({required this.onTap});
 

lib/features/main/main_shell_page.dart

@@ -2,6 +2,8 @@ import 'package:flutter/material.dart';
 import 'package:patbond_flutter/analytics/analytics_page_name.dart';
 import 'package:patbond_flutter/analytics/page_view_tracker.dart';
 import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/features/community/community_controller.dart';
+import 'package:patbond_flutter/features/community/feed_analytics.dart';
 import 'package:patbond_flutter/features/create/create_page.dart';
 import 'package:patbond_flutter/features/home/home_page.dart';
 import 'package:patbond_flutter/features/pets/health_record_analytics.dart';
@@ -19,9 +21,11 @@ class MainShellPage extends StatefulWidget {
   const MainShellPage({
     required this.appState,
     required this.petsController,
+    required this.communityController,
     super.key,
     this.petAnalytics,
     this.healthRecordAnalytics,
+    this.feedAnalytics,
     this.pageViewTracker,
     this.onLogout,
   });
@@ -31,12 +35,18 @@ class MainShellPage extends StatefulWidget {
   /// 宠物档案状态（T2-11 拆出的独立 pets feature；档案 Tab 数据源）。
   final PetsController petsController;
 
+  /// 社区状态（T3-12 数据层；首页 Feed segment 数据源，T3-14 接线）。
+  final CommunityController communityController;
+
   /// pet 域埋点强类型封装（建宠漏斗三事件）。
   final PetAnalytics? petAnalytics;
 
   /// health_record 域埋点强类型封装（T2-13 创建漏斗三事件 + viewed）。
   final HealthRecordAnalytics? healthRecordAnalytics;
 
+  /// feed 域埋点（T3-14 聚合曝光 + 加载失败）。
+  final FeedAnalytics? feedAnalytics;
+
   /// Tab 曝光补点（IndexedStack 切换不产生路由事件，03 号评估 §3.2）。
   final PageViewTracker? pageViewTracker;
 
@@ -107,7 +117,9 @@ class _MainShellPageState extends State<MainShellPage> {
         final pages = [
           HomePage(
             appState: widget.appState,
-            onOpenPost: openPost,
+            communityController: widget.communityController,
+            feedAnalytics: widget.feedAnalytics,
+            isActive: currentIndex == 0,
             onOpenServices: openServices,
             onOpenCreate: () => selectTab(1),
           ),

lib/widgets/common.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:patbond_flutter/core/network/signed_network_image.dart';
 import 'package:patbond_flutter/core/theme/app_theme.dart';
 
 class RemoteImage extends StatelessWidget {
@@ -21,8 +22,10 @@ class RemoteImage extends StatelessWidget {
   Widget build(BuildContext context) {
     return ClipRRect(
       borderRadius: borderRadius,
-      child: Image.network(
-        url,
+      // 缓存 key 剥离预签名参数（T3-14）：媒体 URL 每次响应现签，
+      // 按完整 URL 缓存会同图重复下载。
+      child: Image(
+        image: SignedNetworkImage(url),
         width: width,
         height: height,
         fit: fit,

pubspec.lock

@@ -174,6 +174,11 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_driver:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   flutter_image_compress:
     dependency: "direct main"
     description:
@@ -296,6 +301,11 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  fuchsia_remote_debug_protocol:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   hooks:
     dependency: transitive
     description:
@@ -384,6 +394,11 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.2.2"
+  integration_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   jni:
     dependency: transitive
     description:
@@ -584,6 +599,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.8"
+  process:
+    dependency: transitive
+    description:
+      name: process
+      sha256: "4242ba3508d37e01808bdf71ad1d5bb93a8d671bf2e7450e6b1b353fb0808891"
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.0.6"
   pub_semver:
     dependency: transitive
     description:
@@ -693,6 +716,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.4.1"
+  sync_http:
+    dependency: transitive
+    description:
+      name: sync_http
+      sha256: "7f0cd72eca000d2e026bcd6f990b81d0ca06022ef4e32fb257b30d3d1014a961"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.3.1"
   term_glyph:
     dependency: transitive
     description:
@@ -749,6 +780,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.1.1"
+  webdriver:
+    dependency: transitive
+    description:
+      name: webdriver
+      sha256: "2f3a14ca026957870cfd9c635b83507e0e51d8091568e90129fbf805aba7cade"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.0"
   win32:
     dependency: transitive
     description:

pubspec.yaml

@@ -47,6 +47,9 @@ dependencies:
 dev_dependencies:
   flutter_test:
     sdk: flutter
+  # T3-14 compose 真链路桌面实测入口（integration_test/，环境变量门控）。
+  integration_test:
+    sdk: flutter
   # 定时冲刷/退避测试的假时钟驱动（flutter_test 传递依赖显式声明）。
   fake_async: ^1.3.3
 

test/core/network/signed_network_image_test.dart

@@ -0,0 +1,70 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:patbond_flutter/core/network/signed_network_image.dart';
+
+void main() {
+  group('presignedImageCacheKey', () {
+    test('剥离全部 X-Amz-* 签名参数（大小写不敏感）', () {
+      const url =
+          'http://127.0.0.1:9000/patbond-media/post_image/a-1.jpg'
+          '?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=cred'
+          '&X-Amz-Date=20260909T000000Z&X-Amz-Expires=3600'
+          '&X-Amz-SignedHeaders=host&x-amz-signature=deadbeef';
+      expect(
+        presignedImageCacheKey(url),
+        'http://127.0.0.1:9000/patbond-media/post_image/a-1.jpg',
+      );
+    });
+
+    test('保留非签名 query 参数', () {
+      const url = 'https://cdn.example.com/p.jpg?w=300&X-Amz-Signature=sig';
+      expect(
+        presignedImageCacheKey(url),
+        'https://cdn.example.com/p.jpg?w=300',
+      );
+    });
+
+    test('无签名参数原样返回', () {
+      expect(
+        presignedImageCacheKey('https://cdn.example.com/p.jpg?w=300&q=80'),
+        'https://cdn.example.com/p.jpg?w=300&q=80',
+      );
+      expect(
+        presignedImageCacheKey('https://cdn.example.com/p.jpg'),
+        'https://cdn.example.com/p.jpg',
+      );
+    });
+
+    test('非法 URL 不炸，退回原串', () {
+      expect(presignedImageCacheKey('::not a url::'), '::not a url::');
+    });
+  });
+
+  group('SignedNetworkImage', () {
+    test('同对象不同签名 → 判等（命中同一 ImageCache 条目）', () {
+      final first = SignedNetworkImage(
+        'http://127.0.0.1:9000/m/a.jpg?X-Amz-Signature=sig1&X-Amz-Date=d1',
+      );
+      final second = SignedNetworkImage(
+        'http://127.0.0.1:9000/m/a.jpg?X-Amz-Signature=sig2&X-Amz-Date=d2',
+      );
+      expect(first, second);
+      expect(first.hashCode, second.hashCode);
+    });
+
+    test('不同对象 → 不判等', () {
+      final first = SignedNetworkImage(
+        'http://127.0.0.1:9000/m/a.jpg?X-Amz-Signature=sig',
+      );
+      final second = SignedNetworkImage(
+        'http://127.0.0.1:9000/m/b.jpg?X-Amz-Signature=sig',
+      );
+      expect(first, isNot(second));
+    });
+
+    test('scale 参与判等', () {
+      final first = SignedNetworkImage('http://h/m/a.jpg');
+      final second = SignedNetworkImage('http://h/m/a.jpg', scale: 2);
+      expect(first, isNot(second));
+    });
+  });
+}

test/core/widgets/post_card_test.dart

@@ -0,0 +1,102 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/core/widgets/like_button.dart';
+import 'package:patbond_flutter/core/widgets/post_card.dart';
+import 'package:patbond_flutter/core/widgets/post_media_grid.dart';
+import 'package:patbond_flutter/features/community/community_models.dart';
+import 'package:patbond_flutter/widgets/common.dart';
+
+import '../../helpers/community_test_helpers.dart';
+
+FeedCard cardFrom(Map<String, dynamic> overrides) =>
+    FeedCard.fromJson({...sampleFeedCardJson(), ...overrides});
+
+Widget wrap(Widget child) => MaterialApp(
+  theme: buildAppTheme(),
+  home: Scaffold(body: SingleChildScrollView(child: child)),
+);
+
+void main() {
+  testWidgets('单图形态：通栏 4:3 出血，不走九宫格，预览 2 行', (tester) async {
+    final card = cardFrom({'mediaCount': 1});
+    await tester.pumpWidget(wrap(PostCard(card: card)));
+
+    expect(find.byType(AspectRatio), findsOneWidget);
+    expect(find.byType(PostMediaGrid), findsNothing);
+    final preview = tester.widget<Text>(find.text('晒了一下午太阳。'));
+    expect(preview.maxLines, 2);
+  });
+
+  testWidgets('多图形态：九宫格折叠封面 + 「+N」角标（契约只带封面与计数）', (tester) async {
+    final card = cardFrom({'mediaCount': 5});
+    await tester.pumpWidget(wrap(PostCard(card: card)));
+
+    expect(find.byType(PostMediaGrid), findsOneWidget);
+    expect(find.text('+4'), findsOneWidget);
+  });
+
+  testWidgets('纯文字形态：无媒体区，正文放宽 6 行、15/1.6', (tester) async {
+    final card = cardFrom({'coverImage': null, 'mediaCount': 0});
+    await tester.pumpWidget(wrap(PostCard(card: card)));
+
+    expect(find.byType(PostMediaGrid), findsNothing);
+    expect(find.byType(AspectRatio), findsNothing);
+    final preview = tester.widget<Text>(find.text('晒了一下午太阳。'));
+    expect(preview.maxLines, 6);
+    expect(preview.style?.fontSize, 15);
+  });
+
+  testWidgets('头部行：作者名 + 相对时间；求助帖追加 accent 标', (tester) async {
+    final card = cardFrom({
+      'category': 'help',
+      'publishedAt': DateTime.now()
+          .subtract(const Duration(hours: 2))
+          .toUtc()
+          .toIso8601String(),
+    });
+    await tester.pumpWidget(wrap(PostCard(card: card)));
+
+    expect(find.text('毛毛的铲屎官'), findsOneWidget);
+    expect(find.text('2 小时前'), findsOneWidget);
+    expect(find.widgetWithText(TagPill, '求助'), findsOneWidget);
+  });
+
+  testWidgets('降级作者：占位头像 + 「宠友」默认名', (tester) async {
+    final card = cardFrom({
+      'author': sampleAuthorJson(nickname: null, avatarUrl: null),
+    });
+    await tester.pumpWidget(wrap(PostCard(card: card)));
+
+    expect(find.text('宠友'), findsOneWidget);
+    expect(find.text('毛毛的铲屎官'), findsNothing);
+  });
+
+  testWidgets('操作行：计数与激活态展示；T3-14 纯展示点按无副作用', (tester) async {
+    final card = cardFrom({
+      'likedByMe': true,
+      'likeCount': 6,
+      'bookmarkedByMe': false,
+      'bookmarkCount': 2,
+      'commentCount': 3,
+    });
+    await tester.pumpWidget(wrap(PostCard(card: card)));
+
+    expect(find.text('6'), findsOneWidget);
+    expect(find.text('2'), findsOneWidget);
+    expect(find.text('3'), findsOneWidget);
+    // 点赞激活：实心 favorite + error 色（Colors.red 修订 D6）。
+    final likeIcon = tester.widget<Icon>(find.byIcon(Icons.favorite));
+    expect(likeIcon.color, AppColors.error);
+    // 收藏未激活：描边 + inkSoft。
+    final bookmarkIcon = tester.widget<Icon>(
+      find.byIcon(Icons.bookmark_border),
+    );
+    expect(bookmarkIcon.color, AppColors.inkSoft);
+
+    // 回调未接（null）：点按不抛错、无状态变化。
+    await tester.tap(find.byType(LikeButton).first, warnIfMissed: false);
+    await tester.pump();
+    expect(find.byIcon(Icons.favorite), findsOneWidget);
+  });
+}

test/core/widgets/post_media_grid_test.dart

@@ -0,0 +1,100 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/core/widgets/feed_skeleton.dart';
+import 'package:patbond_flutter/core/widgets/post_media_grid.dart';
+import 'package:patbond_flutter/widgets/common.dart';
+
+Widget wrap(Widget child, {bool disableAnimations = false}) => MaterialApp(
+  theme: buildAppTheme(),
+  home: MediaQuery(
+    data: MediaQueryData(disableAnimations: disableAnimations),
+    child: Scaffold(body: SingleChildScrollView(child: child)),
+  ),
+);
+
+List<String> urls(int count) => List.generate(
+  count,
+  (i) => 'https://minio.local/p$i.jpg?X-Amz-Signature=s',
+);
+
+void main() {
+  group('PostMediaGrid 列数规则（05 §3.2）', () {
+    test('2、4 图 → 2 列；3、5–9 图 → 3 列', () {
+      expect(PostMediaGrid.columnsFor(2), 2);
+      expect(PostMediaGrid.columnsFor(4), 2);
+      expect(PostMediaGrid.columnsFor(3), 3);
+      for (var n = 5; n <= 9; n++) {
+        expect(PostMediaGrid.columnsFor(n), 3);
+      }
+    });
+
+    testWidgets('4 图渲染 4 格网格', (tester) async {
+      await tester.pumpWidget(wrap(PostMediaGrid(urls: urls(4))));
+      expect(find.byType(RemoteImage), findsNWidgets(4));
+      expect(find.byType(GridView), findsOneWidget);
+    });
+
+    testWidgets('超 9 图折叠：显 9 格，末格 ink 80% scrim + 「+N」', (tester) async {
+      await tester.pumpWidget(
+        wrap(PostMediaGrid(urls: urls(12), totalCount: 12)),
+      );
+      expect(find.byType(RemoteImage), findsNWidgets(9));
+      expect(find.text('+3'), findsOneWidget);
+      final scrim = tester
+          .widgetList<DecoratedBox>(find.byType(DecoratedBox))
+          .map((w) => w.decoration)
+          .whereType<BoxDecoration>()
+          .where((d) => d.color == AppColors.ink.withAlpha(204));
+      expect(scrim, isNotEmpty);
+    });
+
+    testWidgets('单图折叠形态（Feed 封面 + 总数）：4:3 单格 + 角标胶囊', (tester) async {
+      await tester.pumpWidget(
+        wrap(PostMediaGrid(urls: urls(1), totalCount: 3)),
+      );
+      expect(find.byType(GridView), findsNothing);
+      expect(find.byType(AspectRatio), findsOneWidget);
+      expect(find.text('+2'), findsOneWidget);
+    });
+
+    testWidgets('单图无折余不出角标', (tester) async {
+      await tester.pumpWidget(wrap(PostMediaGrid(urls: urls(1))));
+      expect(find.textContaining('+'), findsNothing);
+    });
+  });
+
+  group('FeedSkeleton（05 §3.7）', () {
+    testWidgets('骨架单元：头部圆 + 4:3 块 + 正文横条，呼吸动效运行', (tester) async {
+      await tester.pumpWidget(wrap(const FeedSkeleton()));
+      await tester.pump(const Duration(milliseconds: 300));
+      expect(find.byType(AspectRatio), findsOneWidget);
+      final fade = tester.widget<FadeTransition>(
+        find
+            .descendant(
+              of: find.byType(FeedSkeleton),
+              matching: find.byType(FadeTransition),
+            )
+            .first,
+      );
+      final controller = fade.opacity as AnimationController;
+      expect(controller.isAnimating, isTrue);
+    });
+
+    testWidgets('系统减弱动态效果：动画静止在 1.0（pumpAndSettle 可收敛）', (tester) async {
+      await tester.pumpWidget(
+        wrap(const FeedSkeleton(), disableAnimations: true),
+      );
+      await tester.pumpAndSettle();
+      final fade = tester.widget<FadeTransition>(
+        find
+            .descendant(
+              of: find.byType(FeedSkeleton),
+              matching: find.byType(FadeTransition),
+            )
+            .first,
+      );
+      expect(fade.opacity.value, 1.0);
+    });
+  });
+}

test/features/community/feed_analytics_test.dart

@@ -0,0 +1,92 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:patbond_flutter/core/network/api_exception.dart';
+import 'package:patbond_flutter/features/community/feed_analytics.dart';
+
+void main() {
+  late List<(String, Map<String, dynamic>?)> events;
+  late FeedAnalytics analytics;
+
+  setUp(() {
+    events = [];
+    analytics = FeedAnalytics(
+      (name, [props]) async => events.add((name, props)),
+    );
+  });
+
+  test('feed_viewed：五个专有属性逐一上报（06 §1.4 白名单）', () {
+    analytics.feedViewed(
+      feedTab: FeedTab.home,
+      durationMs: 12345,
+      impressionCount: 7,
+      loadMoreCount: 2,
+      refreshCount: 1,
+    );
+
+    expect(events, hasLength(1));
+    expect(events.single.$1, 'feed_viewed');
+    expect(events.single.$2, {
+      'feedTab': 'home',
+      'durationMs': 12345,
+      'impressionCount': 7,
+      'loadMoreCount': 2,
+      'refreshCount': 1,
+    });
+  });
+
+  test('feed_load_failed：业务码带 errorCode 并推导 httpStatus', () {
+    analytics.feedLoadFailed(
+      feedTab: FeedTab.home,
+      loadType: FeedLoadType.loadMore,
+      reason: FeedLoadFailureReason.serverError,
+      errorCode: 40403,
+    );
+
+    expect(events.single.$1, 'feed_load_failed');
+    expect(events.single.$2, {
+      'feedTab': 'home',
+      'loadType': 'load_more',
+      'failureReason': 'server_error',
+      'errorCode': 40403,
+      'httpStatus': 404,
+    });
+  });
+
+  test('feed_load_failed：网络错误缺席 errorCode/httpStatus', () {
+    analytics.feedLoadFailedFrom(
+      const ApiNetworkException(),
+      feedTab: FeedTab.home,
+      loadType: FeedLoadType.refresh,
+    );
+
+    expect(events.single.$2, {
+      'feedTab': 'home',
+      'loadType': 'refresh',
+      'failureReason': 'network_error',
+    });
+  });
+
+  test('异常映射：限流/网络/业务兜底；会话失效不上报', () {
+    expect(
+      feedLoadFailureReasonOf(const ApiRateLimitException()),
+      FeedLoadFailureReason.rateLimited,
+    );
+    expect(
+      feedLoadFailureReasonOf(const ApiNetworkException()),
+      FeedLoadFailureReason.networkError,
+    );
+    expect(
+      feedLoadFailureReasonOf(
+        const ApiBusinessException(code: 40000, message: 'x'),
+      ),
+      FeedLoadFailureReason.serverError,
+    );
+    expect(feedLoadFailureReasonOf(const SessionExpiredException()), isNull);
+
+    analytics.feedLoadFailedFrom(
+      const SessionExpiredException(),
+      feedTab: FeedTab.home,
+      loadType: FeedLoadType.refresh,
+    );
+    expect(events, isEmpty);
+  });
+}

test/features/community/feed_exposure_test.dart

@@ -0,0 +1,77 @@
+import 'package:fake_async/fake_async.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:patbond_flutter/features/community/feed_exposure.dart';
+
+void main() {
+  test('曝光判定：≥50% 驻留满 500ms 记一次，段内按帖去重', () {
+    fakeAsync((async) {
+      final segment = FeedViewSegment(now: async.getClock(DateTime(2026)).now);
+      segment.updateVisibility('p-1', 0.8);
+      async.elapse(const Duration(milliseconds: 600));
+      expect(segment.impressionCount, 1);
+
+      // 再次可见不重复计。
+      segment.updateVisibility('p-1', 0.9);
+      async.elapse(const Duration(milliseconds: 600));
+      expect(segment.impressionCount, 1);
+    });
+  });
+
+  test('快速滑过（<500ms 跌破阈值）不计曝光', () {
+    fakeAsync((async) {
+      final segment = FeedViewSegment(now: async.getClock(DateTime(2026)).now);
+      segment.updateVisibility('p-1', 0.8);
+      async.elapse(const Duration(milliseconds: 300));
+      segment.updateVisibility('p-1', 0.2); // 滚出视口
+      async.elapse(const Duration(seconds: 1));
+      expect(segment.impressionCount, 0);
+    });
+  });
+
+  test('可见面积不足 50% 不起计时', () {
+    fakeAsync((async) {
+      final segment = FeedViewSegment(now: async.getClock(DateTime(2026)).now);
+      segment.updateVisibility('p-1', 0.49);
+      async.elapse(const Duration(seconds: 1));
+      expect(segment.impressionCount, 0);
+    });
+  });
+
+  test('结算：冻结计数、取消在途驻留、幂等只出一份', () {
+    fakeAsync((async) {
+      final clock = async.getClock(DateTime(2026));
+      final segment = FeedViewSegment(now: clock.now);
+      segment.updateVisibility('p-1', 1);
+      async.elapse(const Duration(milliseconds: 600));
+      segment.updateVisibility('p-2', 1); // 在途驻留，结算时未满 500ms
+      async.elapse(const Duration(milliseconds: 100));
+      segment.recordRefresh();
+      segment.recordLoadMore();
+      segment.recordLoadMore();
+
+      final summary = segment.settle();
+      expect(summary, isNotNull);
+      expect(summary!.impressionCount, 1);
+      expect(summary.refreshCount, 1);
+      expect(summary.loadMoreCount, 2);
+      expect(summary.durationMs, 700);
+
+      // 幂等：二次结算无第二条；结算后计数与曝光全部作废。
+      expect(segment.settle(), isNull);
+      segment.updateVisibility('p-3', 1);
+      async.elapse(const Duration(seconds: 1));
+      expect(segment.impressionCount, 1);
+    });
+  });
+
+  test('durationMs 上限截断 30 分钟（防挂机污染 H8）', () {
+    fakeAsync((async) {
+      final segment = FeedViewSegment(now: async.getClock(DateTime(2026)).now);
+      async.elapse(const Duration(minutes: 45));
+      expect(
+        segment.settle()!.durationMs,
+        const Duration(minutes: 30).inMilliseconds,
+      );
+    });
+  });
+}

test/features/home/home_page_test.dart

@@ -0,0 +1,393 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:patbond_flutter/core/network/api_exception.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/core/widgets/feed_skeleton.dart';
+import 'package:patbond_flutter/core/widgets/inline_error_banner.dart';
+import 'package:patbond_flutter/core/widgets/post_card.dart';
+import 'package:patbond_flutter/features/community/community_controller.dart';
+import 'package:patbond_flutter/features/community/community_models.dart';
+import 'package:patbond_flutter/features/community/feed_analytics.dart';
+import 'package:patbond_flutter/features/home/home_page.dart';
+import 'package:patbond_flutter/state/app_state.dart';
+
+import '../../helpers/community_test_helpers.dart';
+
+/// 短卡（纯文字）便于视口内多卡曝光断言；内容带 id 便于查重。
+FeedCard textCard(String id) => FeedCard.fromJson({
+  ...sampleFeedCardJson(id: id),
+  'coverImage': null,
+  'mediaCount': 0,
+  'title': null,
+  'contentPreview': '动态内容 $id',
+});
+
+FeedCard degradedCard(String id) => FeedCard.fromJson({
+  ...sampleFeedCardJson(id: id),
+  'coverImage': null,
+  'mediaCount': 0,
+  'title': null,
+  'contentPreview': '动态内容 $id',
+  'author': sampleAuthorJson(nickname: null, avatarUrl: null),
+});
+
+void main() {
+  late FakeCommunityRepository repository;
+  late CommunityController controller;
+  late List<(String, Map<String, dynamic>?)> events;
+  late FeedAnalytics analytics;
+  late int createTaps;
+
+  setUp(() {
+    repository = FakeCommunityRepository();
+    controller = CommunityController(repository: repository);
+    events = [];
+    analytics = FeedAnalytics(
+      (name, [props]) async => events.add((name, props)),
+    );
+    createTaps = 0;
+  });
+
+  List<Map<String, dynamic>?> eventsNamed(String name) =>
+      events.where((e) => e.$1 == name).map((e) => e.$2).toList();
+
+  Future<void> pumpHome(WidgetTester tester, {bool isActive = true}) {
+    return tester.pumpWidget(
+      MaterialApp(
+        theme: buildAppTheme(),
+        home: Scaffold(
+          body: HomePage(
+            appState: AppState(),
+            communityController: controller,
+            feedAnalytics: analytics,
+            isActive: isActive,
+            onOpenServices: (_) {},
+            onOpenCreate: () => createTaps++,
+          ),
+        ),
+      ),
+    );
+  }
+
+  // 页面纵向主列表（story 环是嵌套的水平 ListView，取 first 即外层）。
+  Finder list() => find.byType(ListView).first;
+
+  testWidgets('四态 · loading：首载渲染 3 张骨架屏', (tester) async {
+    final completer = Completer<CursorPage<FeedCard>>();
+    repository.onFeed = (_, _) => completer.future;
+
+    await pumpHome(tester);
+    await tester.pump();
+
+    // 首载骨架连排 3 张（列表懒加载，视口内至少 1 张被实例化）。
+    expect(find.byType(FeedSkeleton), findsAtLeastNWidgets(1));
+
+    completer.complete(feedPage(const []));
+    await tester.pumpAndSettle();
+    expect(find.byType(FeedSkeleton), findsNothing);
+  });
+
+  testWidgets('四态 · empty：空态插画 + 「发布第一条」CTA 去创作', (tester) async {
+    repository.onFeed = (_, _) async => feedPage(const []);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    expect(find.text('还没有动态'), findsOneWidget);
+    await tester.drag(list(), const Offset(0, -300));
+    await tester.pump();
+    await tester.tap(find.text('发布第一条'));
+    expect(createTaps, 1);
+  });
+
+  testWidgets('四态 · error：横幅 + 重试恢复 ready，feed_load_failed 上报', (tester) async {
+    var attempts = 0;
+    repository.onFeed = (_, _) async {
+      attempts += 1;
+      if (attempts == 1) throw const ApiNetworkException();
+      return feedPage([textCard('p-1')]);
+    };
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    expect(find.byType(InlineErrorBanner), findsOneWidget);
+    expect(find.text('网络异常，请检查网络后重试'), findsOneWidget);
+    expect(eventsNamed('feed_load_failed'), [
+      {
+        'feedTab': 'home',
+        'loadType': 'refresh',
+        'failureReason': 'network_error',
+      },
+    ]);
+
+    await tester.drag(list(), const Offset(0, -200));
+    await tester.pump();
+    await tester.tap(find.text('重试'));
+    await tester.pumpAndSettle();
+
+    expect(find.byType(InlineErrorBanner), findsNothing);
+    expect(find.text('动态内容 p-1'), findsOneWidget);
+  });
+
+  testWidgets('四态 · ready：卡片列表 + 降级作者「宠友」占位', (tester) async {
+    repository.onFeed = (_, _) async =>
+        feedPage([textCard('p-1'), degradedCard('p-2')]);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+    await tester.drag(list(), const Offset(0, -400));
+    await tester.pump();
+
+    expect(find.byType(PostCard), findsNWidgets(2));
+    expect(find.text('毛毛的铲屎官'), findsOneWidget);
+    expect(find.text('宠友'), findsOneWidget);
+  });
+
+  testWidgets('翻页：触底携游标加载下一页，不丢不重，到底显「没有更多了」', (tester) async {
+    final page2 = Completer<CursorPage<FeedCard>>();
+    repository.onFeed = (_, cursor) async {
+      if (cursor == null) {
+        return feedPage(
+          [textCard('p-1'), textCard('p-2')],
+          nextCursor: 'c1',
+          hasMore: true,
+        );
+      }
+      return page2.future;
+    };
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    // 触底：尾部 loading 转圈。
+    await tester.drag(list(), const Offset(0, -1000));
+    await tester.pump();
+    expect(find.byType(CircularProgressIndicator), findsOneWidget);
+
+    page2.complete(feedPage([textCard('p-3')]));
+    await tester.pumpAndSettle();
+    await tester.drag(list(), const Offset(0, -600));
+    await tester.pump();
+
+    // keyset 游标不丢不重：三帖各恰一张，游标原样带出。
+    expect(repository.calls.where((c) => c.startsWith('feed:')).toList(), [
+      'feed:cursor=null',
+      'feed:cursor=c1',
+    ]);
+    expect(find.text('动态内容 p-1'), findsOneWidget);
+    expect(find.text('动态内容 p-2'), findsOneWidget);
+    expect(find.text('动态内容 p-3'), findsOneWidget);
+    expect(find.text('没有更多了'), findsOneWidget);
+  });
+
+  testWidgets('尾部失败：重试条 + feed_load_failed(load_more)，点按重试补页', (tester) async {
+    var page2Attempts = 0;
+    repository.onFeed = (_, cursor) async {
+      if (cursor == null) {
+        return feedPage([textCard('p-1')], nextCursor: 'c1', hasMore: true);
+      }
+      page2Attempts += 1;
+      if (page2Attempts == 1) {
+        throw const ApiBusinessException(code: 40000, message: 'x');
+      }
+      return feedPage([textCard('p-2')]);
+    };
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+    await tester.drag(list(), const Offset(0, -1000));
+    await tester.pumpAndSettle();
+
+    expect(find.text('加载失败，点此重试'), findsOneWidget);
+    expect(eventsNamed('feed_load_failed'), [
+      {
+        'feedTab': 'home',
+        'loadType': 'load_more',
+        'failureReason': 'server_error',
+        'errorCode': 40000,
+        'httpStatus': 400,
+      },
+    ]);
+
+    await tester.tap(find.text('加载失败，点此重试'));
+    await tester.pumpAndSettle();
+    await tester.drag(list(), const Offset(0, -400));
+    await tester.pump();
+    expect(find.text('动态内容 p-2'), findsOneWidget);
+    expect(find.text('加载失败，点此重试'), findsNothing);
+  });
+
+  testWidgets('下拉刷新：整体替换列表；刷新失败保留旧列表 + SnackBar', (tester) async {
+    var attempts = 0;
+    repository.onFeed = (_, _) async {
+      attempts += 1;
+      if (attempts == 1) return feedPage([textCard('p-1')]);
+      if (attempts == 2) throw const ApiNetworkException();
+      return feedPage([textCard('p-9')]);
+    };
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+    expect(find.text('动态内容 p-1'), findsOneWidget);
+
+    // 第一次下拉：失败——旧列表保留、SnackBar 轻提示、事件上报。
+    await tester.fling(list(), const Offset(0, 400), 1000);
+    await tester.pumpAndSettle();
+    expect(find.text('动态内容 p-1'), findsOneWidget);
+    expect(find.text('网络异常，请检查网络后重试'), findsOneWidget);
+    expect(eventsNamed('feed_load_failed').single?['loadType'], 'refresh');
+
+    // 第二次下拉：成功——整体替换不残留旧卡。
+    await tester.fling(list(), const Offset(0, 400), 1000);
+    await tester.pumpAndSettle();
+    expect(find.text('动态内容 p-9'), findsOneWidget);
+    expect(find.text('动态内容 p-1'), findsNothing);
+  });
+
+  testWidgets('曝光结算 · 切走 Tab：可见 ≥500ms 的卡片计入，一段恰一条 feed_viewed', (
+    tester,
+  ) async {
+    repository.onFeed = (_, _) async =>
+        feedPage([textCard('p-1'), textCard('p-2')]);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+    await tester.drag(list(), const Offset(0, -1000));
+    // 先渲染一帧（滚动后位置在帧末扫描），再驻留满 500ms（曝光判定），
+    // 随后切走 Tab 结算。
+    await tester.pump();
+    await tester.pump(const Duration(milliseconds: 600));
+
+    expect(eventsNamed('feed_viewed'), isEmpty);
+    await pumpHome(tester, isActive: false);
+    await tester.pump();
+
+    final viewed = eventsNamed('feed_viewed');
+    expect(viewed, hasLength(1));
+    expect(viewed.single?['feedTab'], 'home');
+    expect(viewed.single?['impressionCount'], 2);
+    // 首屏自动预取不计刷新，本段无翻页。
+    expect(viewed.single?['refreshCount'], 0);
+    expect(viewed.single?['loadMoreCount'], 0);
+    // durationMs 取真实时钟（生产语义），widget 测试的 pump 只推进假
+    // 时钟，此处仅验证字段在场非负（精确口径见 feed_exposure_test）。
+    expect(viewed.single?['durationMs'], greaterThanOrEqualTo(0));
+
+    // 切回 Tab 开新段：再切走仍恰一条新事件（幂等不翻倍）。
+    await pumpHome(tester);
+    await tester.pump();
+    await pumpHome(tester, isActive: false);
+    await tester.pump();
+    expect(eventsNamed('feed_viewed'), hasLength(2));
+  });
+
+  testWidgets('曝光结算 · 快速滑过不计；刷新/翻页计数入段', (tester) async {
+    final cards = List.generate(6, (i) => textCard('p-$i'));
+    repository.onFeed = (_, cursor) async {
+      if (cursor == null) {
+        return feedPage(cards, nextCursor: 'c1', hasMore: true);
+      }
+      return feedPage([textCard('p-6')]);
+    };
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    // 快速滑到底（各卡驻留 <500ms）→ 触发一次翻页。
+    await tester.drag(list(), const Offset(0, -2000));
+    await tester.pumpAndSettle();
+    // 用户下拉刷新一次。
+    await tester.drag(list(), const Offset(0, 2000));
+    await tester.pump();
+    await tester.fling(list(), const Offset(0, 400), 1000);
+    await tester.pumpAndSettle();
+
+    await pumpHome(tester, isActive: false);
+    await tester.pump();
+
+    final viewed = eventsNamed('feed_viewed').single!;
+    expect(viewed['refreshCount'], 1);
+    expect(viewed['loadMoreCount'], 1);
+    // 快速滑过的中段卡片未驻留满 500ms，不应全量计曝光。
+    expect(viewed['impressionCount'], lessThan(cards.length));
+  });
+
+  testWidgets('曝光结算 · 退后台：结算一条，回前台开新段', (tester) async {
+    repository.onFeed = (_, _) async => feedPage([textCard('p-1')]);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.paused);
+    await tester.pump();
+    // 级联 inactive→hidden→paused 只结算一次。
+    expect(eventsNamed('feed_viewed'), hasLength(1));
+
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.resumed);
+    await tester.pump();
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.paused);
+    await tester.pump();
+    expect(eventsNamed('feed_viewed'), hasLength(2));
+
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.hidden);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.inactive);
+    tester.binding.handleAppLifecycleStateChanged(AppLifecycleState.resumed);
+    await tester.pump();
+  });
+
+  testWidgets('曝光结算 · 切到服务分段：结算；切回开新段', (tester) async {
+    repository.onFeed = (_, _) async => feedPage([textCard('p-1')]);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    await tester.tap(find.text('本地服务'));
+    await tester.pump();
+    expect(eventsNamed('feed_viewed'), hasLength(1));
+
+    await tester.tap(find.text('社区动态'));
+    await tester.pump();
+    await tester.tap(find.text('本地服务'));
+    await tester.pump();
+    expect(eventsNamed('feed_viewed'), hasLength(2));
+  });
+
+  testWidgets('T3-14 取舍：整卡点按提示详情接入中（不导航 demo 详情）', (tester) async {
+    repository.onFeed = (_, _) async => feedPage([textCard('p-1')]);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+    await tester.drag(list(), const Offset(0, -600));
+    await tester.pump();
+
+    await tester.tap(find.text('动态内容 p-1'));
+    await tester.pump();
+    expect(find.text('帖子详情正在接入真实数据，敬请期待'), findsOneWidget);
+  });
+
+  testWidgets('搜索词过滤已加载卡片；无命中显搜索空态', (tester) async {
+    repository.onFeed = (_, _) async =>
+        feedPage([textCard('p-1'), textCard('p-2')]);
+
+    await pumpHome(tester);
+    await tester.pumpAndSettle();
+
+    await tester.enterText(find.byType(TextField), 'p-1');
+    await tester.pump();
+    expect(find.byType(PostCard), findsOneWidget);
+
+    await tester.enterText(find.byType(TextField), '不存在的词');
+    await tester.pump();
+    expect(find.byType(PostCard), findsNothing);
+    expect(find.text('没有找到相关动态'), findsOneWidget);
+  });
+}

test/widget_test.dart

@@ -4,6 +4,7 @@ import 'package:patbond_flutter/features/auth/session_manager.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
 import 'helpers/auth_test_helpers.dart';
+import 'helpers/community_test_helpers.dart';
 import 'helpers/pet_test_helpers.dart';
 
 void main() {
@@ -17,6 +18,8 @@ void main() {
         sessionManager: session,
         authRepository: FakeAuthRepository(),
         petsRepository: FakePetsRepository(),
+        communityRepository: FakeCommunityRepository()
+          ..onFeed = (_, _) async => feedPage(const []),
       ),
     );
     await tester.pumpAndSettle();