feat(app): 完善播放协议搜索与空状态

lib/pages/player/player_view_actions.dart

@@ -27,12 +27,14 @@ extension _PlayerViewActions on _PlayerPageState {
         state: PlayerMoreState(
           speed: _playbackSpeed,
           qualities: logic.qualities,
+          selectedQuality: logic.selectedQuality,
         ),
         actions: PlayerMoreActions(
           onSpeedChanged: (value) {
             _updatePlaybackSpeed(value);
             unawaited(logic.setPlaybackSpeed(value));
           },
+          onQualityChanged: (quality) => _switchQuality(context, l10n, quality),
           onClear: _hideChrome,
           onDownload: () => requestEpisodeDownload(context, episode.id),
           onPip: logic.pictureInPicture.isPlatformSupported
@@ -43,6 +45,19 @@ extension _PlayerViewActions on _PlayerPageState {
     );
   }
 
+  Future<bool> _switchQuality(
+    BuildContext context,
+    AppLocalizations l10n,
+    String quality,
+  ) async {
+    Navigator.of(context).pop();
+    final switched = await logic.selectQuality(quality);
+    if (!context.mounted || !switched) return false;
+    final label = quality.toUpperCase() == 'AUTO' ? l10n.qualityAuto : quality;
+    showCenteredToast(context, l10n.qualitySwitched(label));
+    return true;
+  }
+
   Future<void> _openUnlockSheet(
     BuildContext context,
     int index,