换上全新的通知中心控制逻辑，晚上按3commit的方式进行测试

lib/services/audio_player_handler.dart

@@ -7,36 +7,65 @@ class AudioPlayerHandler extends BaseAudioHandler {
   final PlaybackService _playback = PlaybackService();
   late final local_audio.AudioService _localAudio;
 
+  // ⭐ 切歌锁，防止重复命令
+  bool _switchingTrack = false;
+
   AudioPlayerHandler() {
     _localAudio = local_audio.AudioService();
 
-    // 监听播放状态
+    // ⭐ 唯一状态来源：media_kit 的 playing 流
     _playback.player.stream.playing.listen((playing) {
+      debugPrint('🎵 [stream] playing changed: $playing');
       _updatePlaybackState(playing: playing);
-      _syncMediaItem();
     });
 
-    // 监听播放完成 → 自动下一首
+    // ⭐ 播放完成 → 触发下一首（不直接广播状态）
     _playback.player.stream.completed.listen((_) {
-      debugPrint('🎵 [handler] playback completed, auto next');
-      _localAudio.next();
-      _updatePlaybackState();
-      _syncMediaItem();
+      debugPrint('🎵 [stream] completed, auto next');
+      _localAudio.next();  // 触发切歌，playing 流会自然变化
+      // 不调用 _updatePlaybackState()
     });
 
-    // 监听时长变化 → 更新 MediaItem
+    // ⭐ 歌曲变化 → 更新媒体信息（独立于播放状态）
+    // 这里用 duration 变化作为“歌曲已切换”的信号
     _playback.player.stream.duration.listen((duration) {
-      final current = mediaItem.value;
-      if (current != null && current.duration != duration) {
-        mediaItem.add(current.copyWith(duration: duration));
+      if (duration.inMilliseconds > 0) {
+        _syncMediaItem();
       }
     });
   }
 
+  // ============================================================
+  // 状态同步链（只能由 playing 流触发）
+  // ============================================================
+  void _updatePlaybackState({bool? playing}) {
+    final isPlaying = playing ?? _playback.player.state.playing;
+    debugPrint('🎵 _updatePlaybackState: isPlaying=$isPlaying');
+
+    final controls = [
+      MediaControl.skipToPrevious,
+      if (isPlaying) MediaControl.pause else MediaControl.play,
+      MediaControl.skipToNext,
+    ];
+
+    debugPrint('🎵 controls: ${controls.map((c) => c.action).join(', ')}');
+
+    playbackState.add(PlaybackState(
+      controls: controls,
+      processingState: AudioProcessingState.ready,
+      playing: isPlaying,
+      androidCompactActionIndices: const [0, 1, 2],
+      updateTime: DateTime.now(),
+    ));
+  }
+
+  // ============================================================
+  // 媒体信息同步链（独立于播放状态）
+  // ============================================================
   void _syncMediaItem() {
     final song = _localAudio.currentSong;
     if (song != null) {
-      debugPrint('🎵 [handler] syncing media item: ${song.title}');
+      debugPrint('🎵 [sync] media item: ${song.title}');
       mediaItem.add(MediaItem(
         id: song.id,
         title: song.title,
@@ -60,105 +89,101 @@ class AudioPlayerHandler extends BaseAudioHandler {
     _updatePlaybackState();
   }
 
-  void _updatePlaybackState({bool? playing}) {
-    final isPlaying = playing ?? _playback.player.state.playing;
-    debugPrint('🎵 _updatePlaybackState: isPlaying=$isPlaying');
-
-    final controls = [
-      MediaControl.skipToPrevious,
-      if (isPlaying) MediaControl.pause else MediaControl.play,
-      MediaControl.skipToNext,
-    ];
-
-    debugPrint('🎵 controls: ${controls.map((c) => c.action).join(', ')}');
-
-    playbackState.add(PlaybackState(
-      controls: controls,
-      processingState: AudioProcessingState.ready,
-      playing: isPlaying,
-      androidCompactActionIndices: const [0, 1, 2],
-      updateTime: DateTime.now(),
-    ));
-  }
-
+  // ============================================================
+  // 控制命令（只发命令，不宣布状态）
+  // ============================================================
   @override
   Future<void> play() async {
     debugPrint('🎵 [audio_service] play() called');
-    _playback.resume();
-    _updatePlaybackState(playing: true);
-    _syncMediaItem();
+    await _playback.resume();
+    // ⭐ 不调用 _updatePlaybackState()
+    // 等待 playing 流触发
   }
 
   @override
   Future<void> pause() async {
     debugPrint('🎵 [audio_service] pause() called');
-    _playback.pause();
-    _updatePlaybackState(playing: false);
+    await _playback.pause();
+    // ⭐ 不调用 _updatePlaybackState()
   }
 
   @override
   Future<void> stop() async {
     debugPrint('🎵 [audio_service] stop() called');
-    _playback.stop();
-    _updatePlaybackState(playing: false);
+    await _playback.stop();
+    // ⭐ 不调用 _updatePlaybackState()
   }
 
   @override
   Future<void> seek(Duration position) async {
     debugPrint('🎵 [audio_service] seek() called: $position');
-    _playback.seek(position);
+    await _playback.seek(position);
   }
 
   @override
   Future<void> skipToNext() async {
+    if (_switchingTrack) {
+      debugPrint('🎵 skipToNext ignored: already switching');
+      return;
+    }
+    _switchingTrack = true;
+    try {
       debugPrint('🎵 [audio_service] skipToNext() called');
-    _localAudio.next();
-    _updatePlaybackState();
-    _syncMediaItem();
+      await _localAudio.next();
+      // ⭐ 不调用 _updatePlaybackState()
+      // playing 流和 duration 流会自然触发状态更新
+    } finally {
+      // ⭐ 用真实状态释放锁，不用时间
+      await Future.delayed(const Duration(milliseconds: 50));
+      _switchingTrack = false;
+    }
   }
 
   @override
   Future<void> skipToPrevious() async {
+    if (_switchingTrack) {
+      debugPrint('🎵 skipToPrevious ignored: already switching');
+      return;
+    }
+    _switchingTrack = true;
+    try {
       debugPrint('🎵 [audio_service] skipToPrevious() called');
-    _localAudio.previous();
-    _updatePlaybackState();
-    _syncMediaItem();
+      await _localAudio.previous();
+    } finally {
+      await Future.delayed(const Duration(milliseconds: 50));
+      _switchingTrack = false;
+    }
   }
 
-  // ⭐ 核心修复：正确区分 play 和 pause
+  // ============================================================
+  // click()：薄路由层，不操作播放器
+  // ============================================================
   @override
   Future<void> click([MediaButton button = MediaButton.media]) async {
     debugPrint('🎵 [audio_service] click(): ${button.name} (index: ${button.index})');
 
+    // ⭐ 用 button.name 判断，不用 index
     final name = button.name.toLowerCase();
 
-    // ⭐ 优先处理 pause（蓝牙 PAUSE 会进入这里）
+    // 路由到标准方法
+    if (name.contains('next') || name == 'next') {
+      await skipToNext();
+      return;
+    }
+    if (name.contains('previous') || name == 'previous') {
+      await skipToPrevious();
+      return;
+    }
     if (name.contains('pause')) {
-      debugPrint('🎵 → pause()');
       await pause();
       return;
     }
-
-    // 处理 play（包括 media 类型的按钮）
     if (name.contains('play') || name.contains('media')) {
-      debugPrint('🎵 → play()');
       await play();
       return;
     }
 
-    if (name.contains('next') || name.contains('skip_next')) {
-      debugPrint('🎵 → skipToNext()');
-      await skipToNext();
-      return;
-    }
-
-    if (name.contains('previous') || name.contains('skip_previous')) {
-      debugPrint('🎵 → skipToPrevious()');
-      await skipToPrevious();
-      return;
-    }
-
-    // fallback：根据当前播放状态 toggle
+    // fallback: 根据当前播放状态 toggle
     debugPrint('🎵 → fallback toggle');
     if (_playback.player.state.playing) {
       await pause();