fix(player): keep MediaCodec surface alive through MPV teardown

Setting vo=null during disposal could reinitialize MediaCodec and deadlock vendor decoders while the surface was already being released. Terminate libmpv synchronously with its surface references intact, then release the Android surfaces, and cover repeated hardware-decoded teardown on devices.

android/libmpv/src/main/cpp/main.cpp

@@ -23,25 +23,6 @@ extern "C" {
 
 void render_cleanup(JNIEnv* env);
 
-static void* destroy_mpv_thread(void* arg) {
-  mpv_handle* handle = (mpv_handle*)arg;
-  mpv_terminate_destroy(handle);
-  return NULL;
-}
-
-// Fire-and-forget mpv_terminate_destroy on a detached thread.
-// Safe because the event thread has been joined and g_mpv cleared —
-// no other code references this handle.
-static void async_destroy(mpv_handle* handle) {
-  pthread_t tid;
-  if (pthread_create(&tid, NULL, destroy_mpv_thread, handle) == 0) {
-    pthread_detach(tid);
-  } else {
-    // Fallback: destroy synchronously if thread creation fails
-    mpv_terminate_destroy(handle);
-  }
-}
-
 extern "C" {
 jni_func(void, nativeCreate, jobject appctx);
 jni_func(void, nativeInit);
@@ -80,20 +61,17 @@ jni_func(void, nativeCreate, jobject appctx) {
     mpv_wakeup(leaked_mpv);
     pthread_join(event_thread_id, NULL);
     g_mpv = NULL;
+    mpv_terminate_destroy(leaked_mpv);
     render_cleanup(env);
   }
 
   g_mpv = mpv_create();
   if (!g_mpv) {
     die("context init failed");
-    if (leaked_mpv) mpv_terminate_destroy(leaked_mpv);
     return;
   }
 
   mpv_request_log_messages(g_mpv, "v");
-
-  // Async teardown of leaked handle — doesn't block caller
-  if (leaked_mpv) async_destroy(leaked_mpv);
 }
 
 jni_func(void, nativeInit) {
@@ -128,10 +106,11 @@ jni_func(void, nativeDestroy) {
   pthread_join(event_thread_id, NULL);
 
   g_mpv = NULL;
-  render_cleanup(env);
 
-  // Async teardown — nativeDestroy returns immediately
-  async_destroy(local_mpv);
+  // The MediaCodec VO can retain the Surface until final decoder teardown.
+  // Keep its JNI refs alive for the entire blocking termination.
+  mpv_terminate_destroy(local_mpv);
+  render_cleanup(env);
 }
 
 jni_func(void, nativeCommand, jobjectArray jarray) {