fix(playback): prevent native subtitle autoselect

lib/mpv/models.dart

@@ -70,8 +70,23 @@ sealed class SubtitleTrack with _$SubtitleTrack {
     String? uri,
   }) = _SubtitleTrack;
 
-  factory SubtitleTrack.uri(String uri, {String? title, String? language}) =>
-      SubtitleTrack(id: 'external:$uri', title: title, language: language, isExternal: true, uri: uri);
+  factory SubtitleTrack.uri(
+    String uri, {
+    String? title,
+    String? language,
+    String? codec,
+    bool isDefault = false,
+    bool isForced = false,
+  }) => SubtitleTrack(
+    id: 'external:$uri',
+    title: title,
+    language: language,
+    codec: codec,
+    isDefault: isDefault,
+    isForced: isForced,
+    isExternal: true,
+    uri: uri,
+  );
 
   static const auto = SubtitleTrack(id: 'auto', title: 'Auto');
 

lib/mpv/player/platform/player_android.dart

@@ -120,7 +120,16 @@ class PlayerAndroid extends PlayerBase {
       if (externalSubtitles != null && externalSubtitles.isNotEmpty)
         'externalSubtitles': externalSubtitles
             .where((s) => s.uri != null)
-            .map((s) => {'uri': s.uri, 'title': s.title, 'language': s.language})
+            .map(
+              (s) => {
+                'uri': s.uri,
+                'title': s.title,
+                'language': s.language,
+                'codec': s.codec,
+                'isDefault': s.isDefault,
+                'isForced': s.isForced,
+              },
+            )
             .toList(),
     });
   }

lib/mpv/player/player_native.dart

@@ -180,6 +180,11 @@ class PlayerNative extends PlayerBase {
       await setProperty('pause', 'yes');
     }
 
+    // Prevent mpv's own default subtitle selection from racing the
+    // server-backed TrackManager decision applied after tracks are discovered.
+    await setProperty('sid', 'no');
+    await setProperty('secondary-sid', 'no');
+
     // Convert content:// URIs to fdclose:// for MPV on Android (SAF SD card downloads)
     var uri = media.uri;
     if (Platform.isAndroid && uri.startsWith('content://')) {