fix(player): 修复竖滑上一集不自动播放

lib/pages/player/player_view.dart

@@ -2,6 +2,7 @@
 
 import 'dart:async';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:provider/provider.dart';
@@ -124,6 +125,8 @@ class _PlayerPageState extends State<PlayerPage>
   double? _speedBeforeBoost;
   bool? _chromeBeforeBoost;
   DateTime? _lastDoubleTapAt;
+  DateTime? _swipeStartedAt;
+  bool _swipePrewarmCaptured = false;
 
   /// 收藏切换后的本地增量：基准是详情快照，切换成功按服务端状态 ±1。
   final Map<String, int> _favoriteDelta = {};
@@ -308,6 +311,34 @@ class _PlayerPageState extends State<PlayerPage>
     unawaited(logic.setPlaybackSpeed(speed));
   }
 
+  bool _handlePageScroll(ScrollNotification notification) {
+    if (notification is ScrollStartNotification &&
+        notification.dragDetails != null) {
+      _swipeStartedAt = DateTime.now();
+      _swipePrewarmCaptured = false;
+    } else if (notification is ScrollUpdateNotification &&
+        !_swipePrewarmCaptured &&
+        notification.dragDetails != null) {
+      final delta = notification.scrollDelta ?? 0;
+      if (delta != 0) {
+        _swipePrewarmCaptured = true;
+        logic.session.prewarmNeighbors(forward: delta > 0);
+      }
+    } else if (notification is ScrollEndNotification) {
+      _swipePrewarmCaptured = false;
+    }
+    return false;
+  }
+
+  void _logSwipeReveal() {
+    if (!kDebugMode) return;
+    final startedAt = _swipeStartedAt;
+    if (startedAt == null) return;
+    _swipeStartedAt = null;
+    final elapsed = DateTime.now().difference(startedAt).inMilliseconds;
+    debugPrint('[player] swipe reveal ${elapsed}ms');
+  }
+
   Future<void> _refreshHomeFeed() async {
     final refresh = widget.onRefreshFeed;
     if (refresh == null) return;
@@ -420,25 +451,28 @@ class _PlayerPageState extends State<PlayerPage>
     final content = AnimatedBuilder(
       animation: logic.session,
       builder: (context, _) {
-        final pages = PageView.builder(
-          controller: logic.pages,
-          scrollDirection: Axis.vertical,
-          allowImplicitScrolling: true,
-          physics: widget.onRefreshFeed == null
-              ? null
-              : const FeedRefreshPhysics(),
-          itemCount: indices.length,
-          onPageChanged: (position) {
-            final index = indices[position];
-            widget.onDramaChanged?.call(logic.queue.entryAt(index).drama);
-            unawaited(logic.selectEpisode(index));
-            if (position >= indices.length - 3) {
-              final loadMore = widget.onLoadMore;
-              if (loadMore != null) unawaited(loadMore());
-            }
-          },
-          itemBuilder: (context, position) =>
-              _buildEpisode(context, indices[position], interactions),
+        final pages = NotificationListener<ScrollNotification>(
+          onNotification: _handlePageScroll,
+          child: PageView.builder(
+            controller: logic.pages,
+            scrollDirection: Axis.vertical,
+            allowImplicitScrolling: true,
+            physics: widget.onRefreshFeed == null
+                ? null
+                : const FeedRefreshPhysics(),
+            itemCount: indices.length,
+            onPageChanged: (position) {
+              final index = indices[position];
+              widget.onDramaChanged?.call(logic.queue.entryAt(index).drama);
+              unawaited(logic.selectEpisode(index));
+              if (position >= indices.length - 3) {
+                final loadMore = widget.onLoadMore;
+                if (loadMore != null) unawaited(loadMore());
+              }
+            },
+            itemBuilder: (context, position) =>
+                _buildEpisode(context, indices[position], interactions),
+          ),
         );
         if (widget.onRefreshFeed == null) return pages;
         return FeedPullRefresh(
@@ -550,6 +584,7 @@ class _PlayerPageState extends State<PlayerPage>
     final handoffPort = handoff is VideoPlayerPort ? handoff : null;
     // 测试播放器没有纹理。有播放器但不是视频控制器时视为已就绪，避免加载圈一直转。
     final videoReady = videoPort?.controller.value.isInitialized ?? false;
+    if (selected && videoReady) _logSwipeReveal();
     final ready = videoReady || port != null;
     final theater = logic.pip || logic.pipPreparing;
     final locked = logic.session.isLocked || episode.locked;
@@ -577,7 +612,10 @@ class _PlayerPageState extends State<PlayerPage>
           handoff: handoffPort?.controller,
           videoUrl: videoPort?.controller.dataSource ?? episode.videoUrl,
           theater: theater,
-          openingFrame: playerOpeningFrame(episode.thumbnailsUrl),
+          openingFrame: playerOpeningFrame(
+            episode.thumbnailsUrl,
+            posterUrl: drama.posterUrl,
+          ),
         ),
         if (selected &&
             !theater &&