新增：帖子详情页真实数据整页替换——四态/真九宫格大图/评论区/关注双态，Feed 导航与互动全接线，demo 详情退役（T3-15/16）

- post_detail_page 整页重写：内存副本先渲染 + getPost 拉新、四态
 （loading/error+重试/ready/40403 提示后返回 Feed 并刷新）；媒体全量
  ——单图原比例（高度钳制 [0.75w,1.33w]）、多图真九宫格（D11 轮播
  弃用，本单裁定）+ InteractiveViewer 全屏大图（03 号拍板 E）
- 评论区：游标列表触底补页 + 底部输入条创建（幂等键在数据层）+
  仅本人评论渲染删除入口（40301/40404 服务端兜底）；成败埋点对
 （durationMs 取输入会话起点、attemptSeq 会话内递增）；CommentTile
  升共享组件（@ 回复前缀呈现、降级作者「宠友」占位）
- 关注双态钮（tonal ＋关注 / Outlined 已关注 + 取关确认）乐观翻转、
  回滚零动画 + SnackBar，user_followed/unfollowed(post_detail) 挂接；
  本人帖不渲染
- Feed 接通：整卡与评论钮导航详情（T3-14 占位提示移除）、点赞/收藏
  接共享 ToggleSync（详情与卡片同一实例跨页一致）、toggleError
  一次性 SnackBar 消费
- 主壳/装配：openPost 按 postId push；create demo 流不再导航已退役的
  demo 详情（发布页真实化留 T3-17）；AppState 在 post_detail/Feed 面
  消费清零
- compose 冒烟（env 门控默认跳过）：真链路发帖/点赞幂等/收藏/评论/
  删评一轮 + 断网点赞回滚（生产 ApiClient 异常链）

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

lib/app/app.dart

@@ -13,6 +13,7 @@ import 'package:patbond_flutter/features/auth/login_page.dart';
 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_interaction_analytics.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';
@@ -50,6 +51,7 @@ class _AppState extends State<App> {
   late final PetAnalytics petAnalytics;
   late final HealthRecordAnalytics healthRecordAnalytics;
   late final FeedAnalytics feedAnalytics;
+  late final CommunityInteractionAnalytics interactionAnalytics;
   late final SessionTracker _sessionTracker;
   late final AnalyticsService _analytics;
   late final PageViewTracker _pageViewTracker;
@@ -95,9 +97,12 @@ class _AppState extends State<App> {
     petsController = PetsController(
       repository: widget.petsRepository ?? _buildPetsRepository(),
     );
-    // T3-14：Feed segment 接线主壳（数据层 T3-12 就位）。
+    // T3-14：Feed segment 接线主壳（数据层 T3-12 就位）；T3-16 起
+    // 点赞/收藏成功埋点经 interactionAnalytics 在 controller 内上报。
+    interactionAnalytics = CommunityInteractionAnalytics(_analytics.trackEvent);
     communityController = CommunityController(
       repository: widget.communityRepository ?? _buildCommunityRepository(),
+      interactionAnalytics: interactionAnalytics,
     );
     petAnalytics = PetAnalytics(_analytics.trackEvent);
     healthRecordAnalytics = HealthRecordAnalytics(_analytics.trackEvent);
@@ -235,9 +240,11 @@ class _AppState extends State<App> {
           appState: appState,
           petsController: petsController,
           communityController: communityController,
+          currentUserId: sessionManager.userId,
           petAnalytics: petAnalytics,
           healthRecordAnalytics: healthRecordAnalytics,
           feedAnalytics: feedAnalytics,
+          interactionAnalytics: interactionAnalytics,
           pageViewTracker: _pageViewTracker,
           onLogout: authRepository.logout,
         );

lib/core/widgets/comment_tile.dart

@@ -0,0 +1,141 @@
+import 'package:flutter/material.dart';
+import 'package:patbond_flutter/core/theme/app_theme.dart';
+import 'package:patbond_flutter/core/widgets/pet_avatar.dart';
+import 'package:patbond_flutter/features/community/community_display.dart';
+import 'package:patbond_flutter/features/community/community_models.dart';
+
+/// 评论条目（05 号规范 §3.4，demo 气泡形态升共享）：
+/// `PetAvatar sm32` + 10 + 气泡（`surface` 底、`border` 1px、圆角 16、
+/// padding 12）——作者名 13/w700 → 4 → 内容 bodyMedium → 6 → 底行
+/// （时间 11 `inkSoft` + 仅本人评论的「删除」入口）。
+///
+/// - @ 回复（单层平铺，契约 replyToUser）以「回复 @昵称：」前缀呈现；
+///   降级作者统一「宠友」占位（isDegraded 一个判定口）。
+/// - [onDelete] 非 null 才渲染删除入口——**权限判定在调用方**（17 号
+///   后端语义：仅评论作者可删，他人可见评论 403/40301）；[deleting]
+///   期间入口替换为 14 转圈防重复提交。
+/// - 评论点赞（§3.4 底行右端）无契约端点，M3 不渲染。
+class CommentTile extends StatelessWidget {
+  const CommentTile({
+    required this.comment,
+    super.key,
+    this.onDelete,
+    this.deleting = false,
+    this.now,
+  });
+
+  final PostComment comment;
+
+  /// 删除回调；null = 非本人评论，不渲染删除入口。
+  final VoidCallback? onDelete;
+
+  /// 删除请求在途（入口转圈锁定）。
+  final bool deleting;
+
+  /// 相对时间的参考时钟（测试注入；缺省取当前时间）。
+  final DateTime? now;
+
+  @override
+  Widget build(BuildContext context) {
+    final replyTo = comment.replyToUser;
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        PetAvatar(size: PetAvatarSize.sm, url: comment.author.avatarUrl),
+        const SizedBox(width: 10),
+        Expanded(
+          child: Container(
+            padding: const EdgeInsets.all(12),
+            decoration: BoxDecoration(
+              color: AppColors.surface,
+              border: Border.all(color: AppColors.border),
+              borderRadius: BorderRadius.circular(16),
+            ),
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  authorDisplayName(comment.author),
+                  style: const TextStyle(
+                    color: AppColors.ink,
+                    fontSize: 13,
+                    fontWeight: FontWeight.w700,
+                  ),
+                ),
+                const SizedBox(height: 4),
+                Text.rich(
+                  TextSpan(
+                    children: [
+                      if (replyTo != null)
+                        TextSpan(
+                          text: '回复 @${authorDisplayName(replyTo)}：',
+                          style: const TextStyle(
+                            color: AppColors.inkSoft,
+                            fontWeight: FontWeight.w600,
+                          ),
+                        ),
+                      TextSpan(text: comment.content),
+                    ],
+                  ),
+                  style: Theme.of(context).textTheme.bodyMedium,
+                ),
+                const SizedBox(height: 6),
+                Row(
+                  children: [
+                    Text(
+                      feedRelativeTime(comment.createdAt, now: now),
+                      style: const TextStyle(
+                        color: AppColors.inkSoft,
+                        fontSize: 11,
+                      ),
+                    ),
+                    const Spacer(),
+                    if (onDelete != null)
+                      deleting
+                          ? const Padding(
+                              padding: EdgeInsets.all(4),
+                              child: SizedBox(
+                                width: 14,
+                                height: 14,
+                                child: CircularProgressIndicator(
+                                  strokeWidth: 2,
+                                  color: AppColors.inkSoft,
+                                ),
+                              ),
+                            )
+                          : Semantics(
+                              label: '删除评论',
+                              button: true,
+                              child: InkWell(
+                                onTap: onDelete,
+                                borderRadius: BorderRadius.circular(
+                                  AppRadius.pill,
+                                ),
+                                // 视觉 11 字，触控由 padding 撑到 ≥32
+                                //（气泡内行高受限，不足 44 以热区扩展补偿）。
+                                child: const Padding(
+                                  padding: EdgeInsets.symmetric(
+                                    horizontal: 10,
+                                    vertical: 8,
+                                  ),
+                                  child: Text(
+                                    '删除',
+                                    style: TextStyle(
+                                      color: AppColors.inkSoft,
+                                      fontSize: 11,
+                                      fontWeight: FontWeight.w600,
+                                    ),
+                                  ),
+                                ),
+                              ),
+                            ),
+                  ],
+                ),
+              ],
+            ),
+          ),
+        ),
+      ],
+    );
+  }
+}

lib/features/home/home_page.dart

@@ -26,6 +26,7 @@ class HomePage extends StatefulWidget {
     required this.onOpenServices,
     required this.onOpenCreate,
     super.key,
+    this.onOpenPost,
     this.feedAnalytics,
     this.isActive = true,
   });
@@ -38,6 +39,9 @@ class HomePage extends StatefulWidget {
   final ValueChanged<bool> onOpenServices;
   final VoidCallback onOpenCreate;
 
+  /// 帖子详情导航（T3-15 接通；主壳 push PostDetailPage）。
+  final ValueChanged<String>? onOpenPost;
+
   /// feed 域埋点（feed_viewed 聚合曝光 + feed_load_failed）。
   final FeedAnalytics? feedAnalytics;
 
@@ -231,14 +235,6 @@ class _HomePageState extends State<HomePage> with WidgetsBindingObserver {
     }
   }
 
-  /// 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 {
@@ -309,6 +305,17 @@ class _HomePageState extends State<HomePage> with WidgetsBindingObserver {
     return ListenableBuilder(
       listenable: _feed,
       builder: (context, _) {
+        // 点赞/收藏对账失败的一次性 SnackBar（§3.5 回滚提示；与详情页
+        // 共用 controller 的 toggleError 消费口，先消费者清空）。
+        if (_feed.toggleError != null) {
+          _feed.clearToggleError();
+          WidgetsBinding.instance.addPostFrameCallback((_) {
+            if (!mounted) return;
+            ScaffoldMessenger.of(
+              context,
+            ).showSnackBar(const SnackBar(content: Text('操作失败，请重试')));
+          });
+        }
         // 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();
@@ -467,7 +474,15 @@ class _HomePageState extends State<HomePage> with WidgetsBindingObserver {
               padding: const EdgeInsets.only(bottom: 16),
               child: KeyedSubtree(
                 key: _cardKeys.putIfAbsent(card.id, GlobalKey.new),
-                child: PostCard(card: card, onTap: _showDetailPending),
+                // 点赞/收藏经共享 ToggleSync（source=feed 缺省）；整卡与
+                // 评论钮进详情（T3-15 导航接通，T3-14 的占位提示移除）。
+                child: PostCard(
+                  card: card,
+                  onTap: () => widget.onOpenPost?.call(card.id),
+                  onCommentTap: () => widget.onOpenPost?.call(card.id),
+                  onLikeTap: () => _feed.toggleLike(card.id),
+                  onBookmarkTap: () => _feed.toggleBookmark(card.id),
+                ),
               ),
             ),
           // 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）。

lib/features/main/main_shell_page.dart

@@ -3,6 +3,7 @@ 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/community_interaction_analytics.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';
@@ -13,7 +14,6 @@ import 'package:patbond_flutter/features/pets/pets_page.dart';
 import 'package:patbond_flutter/features/post/post_detail_page.dart';
 import 'package:patbond_flutter/features/profile/profile_page.dart';
 import 'package:patbond_flutter/features/services/services_page.dart';
-import 'package:patbond_flutter/models/models.dart';
 import 'package:patbond_flutter/state/app_state.dart';
 import 'package:patbond_flutter/widgets/common.dart';
 
@@ -23,9 +23,11 @@ class MainShellPage extends StatefulWidget {
     required this.petsController,
     required this.communityController,
     super.key,
+    this.currentUserId,
     this.petAnalytics,
     this.healthRecordAnalytics,
     this.feedAnalytics,
+    this.interactionAnalytics,
     this.pageViewTracker,
     this.onLogout,
   });
@@ -38,6 +40,9 @@ class MainShellPage extends StatefulWidget {
   /// 社区状态（T3-12 数据层；首页 Feed segment 数据源，T3-14 接线）。
   final CommunityController communityController;
 
+  /// 当前登录用户 id（详情页评论删除入口 / 关注钮自见性的 UI 判定）。
+  final String? currentUserId;
+
   /// pet 域埋点强类型封装（建宠漏斗三事件）。
   final PetAnalytics? petAnalytics;
 
@@ -47,6 +52,9 @@ class MainShellPage extends StatefulWidget {
   /// feed 域埋点（T3-14 聚合曝光 + 加载失败）。
   final FeedAnalytics? feedAnalytics;
 
+  /// 互动域埋点（T3-16 评论成败对 + 关注对；详情页消费）。
+  final CommunityInteractionAnalytics? interactionAnalytics;
+
   /// Tab 曝光补点（IndexedStack 切换不产生路由事件，03 号评估 §3.2）。
   final PageViewTracker? pageViewTracker;
 
@@ -93,12 +101,18 @@ class _MainShellPageState extends State<MainShellPage> {
     widget.pageViewTracker?.reportTab(_tabPages[3]);
   }
 
-  void openPost(PostModel post) {
+  /// 帖子详情（T3-15：真实数据整页；Feed 卡片与详情共享
+  /// communityController，互动状态跨页一致）。
+  void openPost(String postId) {
     Navigator.of(context).push(
       MaterialPageRoute<void>(
         settings: RouteSettings(name: AnalyticsPageName.postDetail.pageName),
-        builder: (context) =>
-            PostDetailPage(appState: widget.appState, postId: post.id),
+        builder: (context) => PostDetailPage(
+          controller: widget.communityController,
+          postId: postId,
+          currentUserId: widget.currentUserId,
+          analytics: widget.interactionAnalytics,
+        ),
       ),
     );
   }
@@ -122,15 +136,13 @@ class _MainShellPageState extends State<MainShellPage> {
             isActive: currentIndex == 0,
             onOpenServices: openServices,
             onOpenCreate: () => selectTab(1),
+            onOpenPost: openPost,
           ),
           CreatePage(
             appState: widget.appState,
-            onPublished: (post) {
-              selectTab(0);
-              WidgetsBinding.instance.addPostFrameCallback(
-                (_) => openPost(post),
-              );
-            },
+            // demo 详情页已退役（T3-15）：demo 发布流不再导航详情，
+            // 回首页 Feed；发布页真实化随 T3-17 收编。
+            onPublished: (_) => selectTab(0),
           ),
           PetsPage(
             controller: widget.petsController,