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>

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),
           ),