fix(player): 分离首页与播放页播放上下文

lib/core/data/services/playback_neighbors.dart

@@ -69,6 +69,7 @@ Future<void> _placeNeighbor(PlaybackSession session, _PlayerSlot? slot) async {
 
 /// 当前集已经出画后，按手势方向静默准备上一集和下一集。
 void _warmNeighbors(PlaybackSession session, {bool preferredNext = true}) {
+  if (!session.warmNeighborsEnabled) return;
   final request = session._generation;
   final nextTask = _warmOne(session, request, session._nextIndex, next: true);
   final previousTask = _warmOne(

lib/core/data/services/playback_queue.dart

@@ -4,9 +4,6 @@ import '../models/drama.dart';
 
 /// A player session has one navigation meaning: browse dramas or browse episodes.
 class PlaybackQueue {
-  PlaybackQueue.fromEntries(List<PlaybackEntry> entries)
-    : entries = List.unmodifiable(entries);
-
   PlaybackQueue.home(List<Drama> dramas)
     : entries = List.unmodifiable(
         dramas

lib/core/data/services/playback_session.dart

@@ -27,6 +27,7 @@ class PlaybackSession extends ChangeNotifier {
     this.activate,
     PlaybackCoordinator? coordinator,
     this.waitForFrame,
+    this.warmNeighborsEnabled = true,
   }) : _coordinator = coordinator ?? PlaybackCoordinator();
 
   final List<Episode> episodes;
@@ -39,6 +40,7 @@ class PlaybackSession extends ChangeNotifier {
   /// Runs only when a slot becomes current (e.g. progress listeners).
   final PlayerPreparation? activate;
   final Future<void> Function()? waitForFrame;
+  final bool warmNeighborsEnabled;
   final PlaybackCoordinator _coordinator;
   final Set<_PlayerSlot> _live = {};
   _PlayerSlot? _active;
@@ -80,6 +82,8 @@ class PlaybackSession extends ChangeNotifier {
   String? get error => _error;
   // Includes initialization and asynchronous disposal, until native release ends.
   int get livePlayerCount => _live.length;
+  bool get activeSlotActivated => _active?.activated ?? false;
+  bool get activeSlotPlaying => _active?.playing ?? false;
   int? get preloadedIndex => _next?.prepared == true ? _next?.index : null;
   int? get previousPreloadedIndex =>
       _previous?.prepared == true ? _previous?.index : null;
@@ -137,50 +141,9 @@ class PlaybackSession extends ChangeNotifier {
     if (_visible && !_overlayOpen) _warmNeighbors(this);
   }
 
-  /// 在剧维度和集维度之间切换队列，但保留当前 active controller 与播放状态。
-  void remapQueuePreservingActive(
-    List<Episode> nextEpisodes, {
-    required int currentIndex,
-    int? preloadIndex,
-    int? previousIndex,
-    bool notify = true,
-  }) {
-    if (_closed ||
-        currentIndex < 0 ||
-        currentIndex >= nextEpisodes.length ||
-        _active == null) {
-      return;
-    }
-    _generation++;
-    episodes
-      ..clear()
-      ..addAll(nextEpisodes);
-    _active!.index = currentIndex;
-    _currentIndex = currentIndex;
-    _selected = true;
-    _loading = false;
-    _error = null;
-    _rememberNeighbors(preloadIndex, previousIndex);
-    final staleNext = _next;
-    final stalePrevious = _previous;
-    final staleHandoff = _handoff;
-    _next = null;
-    _previous = null;
-    _handoff = null;
-    if (notify) _notify();
-    unawaited(
-      _enqueue(() async {
-        await _retire(staleNext);
-        await _retire(stalePrevious);
-        await _retire(staleHandoff);
-      }),
-    );
-    if (_visible && !_overlayOpen) _warmNeighbors(this);
-  }
-
   void _rememberNeighbors(int? preloadIndex, int? previousIndex) {
-    _nextIndex = preloadIndex;
-    _previousIndex = previousIndex;
+    _nextIndex = warmNeighborsEnabled ? preloadIndex : null;
+    _previousIndex = warmNeighborsEnabled ? previousIndex : null;
   }
 
   Future<void> _enqueue(Future<void> Function() operation) {
@@ -247,10 +210,13 @@ class PlaybackSession extends ChangeNotifier {
     int index, {
     int? preloadIndex,
     int? previousIndex,
+    bool? userWantsPlay,
   }) async {
     if (_closed || index < 0 || index >= episodes.length) return;
     // 切换到不同剧集时恢复播放；仍停留在同一集时保留用户暂停。
-    if (!_selected || index != _currentIndex) {
+    if (userWantsPlay != null) {
+      _userWantsPlay = userWantsPlay;
+    } else if (!_selected || index != _currentIndex) {
       _userWantsPlay = true;
     }
     final request = ++_generation;

lib/core/data/services/playback_session_controls.dart

@@ -6,10 +6,71 @@ part of 'playback_session.dart';
 extension PlaybackSessionControls on PlaybackSession {
   /// 滑动手势开始时按方向优先准备相邻集，不改变当前集播放状态。
   void prewarmNeighbors({required bool forward}) {
-    if (!_visible || _overlayOpen || _active?.prepared != true) return;
+    if (!warmNeighborsEnabled ||
+        !_visible ||
+        _overlayOpen ||
+        _active?.prepared != true) {
+      return;
+    }
     _warmNeighbors(this, preferredNext: forward);
   }
 
+  /// 路由交接时同步暂停当前原生播放器，controller 仍由 session 持有。
+  Future<void> pauseForRouteHandoff() {
+    if (_closed) return Future<void>.value();
+    _routeVisible = false;
+    return _enqueue(() async {
+      final slot = _active;
+      if (slot == null) return;
+      await slot.player.pause();
+      slot.playing = false;
+    });
+  }
+
+  /// 路由恢复可见后立即同步当前 controller，并等待原生播放状态落地。
+  Future<void> resumeForRouteHandoff() {
+    if (_closed) return Future<void>.value();
+    _routeVisible = true;
+    return _enqueue(() async {
+      final slot = _active;
+      if (kDebugMode) {
+        debugPrint(
+          '[feed-handoff] phase=resume slot=${slot?.index} '
+          'activated=${slot?.activated} playing=${slot?.playing} '
+          'retiring=${slot?.retiring} current=$_currentIndex '
+          'visible=$_visible user=$_userWantsPlay loading=$_loading',
+        );
+      }
+      if (slot == null || slot.retiring) return;
+      if (!slot.activated) {
+        try {
+          await activate?.call(episodes[slot.index], slot.player);
+        } catch (error) {
+          if (kDebugMode) {
+            debugPrint('[feed-handoff] phase=activation-failed error=$error');
+          }
+        }
+        if (_closed || _active != slot || slot.retiring) {
+          if (kDebugMode) {
+            debugPrint(
+              '[feed-handoff] phase=activation-aborted closed=$_closed '
+              'activeSame=${identical(_active, slot)} retiring=${slot.retiring}',
+            );
+          }
+          return;
+        }
+        slot.activated = true;
+      }
+      await _applyPlayback(slot);
+      if (kDebugMode) {
+        debugPrint(
+          '[feed-handoff] phase=resumed activated=${slot.activated} '
+          'playing=${slot.playing}',
+        );
+      }
+    });
+  }
+
   /// 选中锁定集时立即停播并释放所有原生播放器，不创建新片源。
   Future<void> selectLocked(
     int index, {