fix: android - execute in background

mobile/pigeon/background_worker_api.dart

@@ -20,10 +20,13 @@ class BackgroundWorkerSettings {
 
 @HostApi()
 abstract class BackgroundWorkerFgHostApi {
+  @async
   void enable();
 
+  @async
   void configure(BackgroundWorkerSettings settings);
 
+  @async
   void disable();
 }
 

mobile/pigeon/background_worker_lock_api.dart

@@ -11,7 +11,9 @@ import 'package:pigeon/pigeon.dart';
 )
 @HostApi()
 abstract class BackgroundWorkerLockApi {
+  @async
   void lock();
 
+  @async
   void unlock();
 }

mobile/pigeon/connectivity_api.dart

@@ -15,6 +15,7 @@ enum NetworkCapability { cellular, wifi, vpn, unmetered }
 
 @HostApi()
 abstract class ConnectivityApi {
+  @async
   @TaskQueue(type: TaskQueueType.serialBackgroundThread)
   List<NetworkCapability> getCapabilities();
 }

mobile/pigeon/native_sync_api.dart

@@ -83,6 +83,7 @@ class HashResult {
 abstract class NativeSyncApi {
   bool shouldFullSync();
 
+  @async
   @TaskQueue(type: TaskQueueType.serialBackgroundThread)
   SyncDelta getMediaChanges();
 
@@ -90,15 +91,19 @@ abstract class NativeSyncApi {
 
   void clearSyncCheckpoint();
 
+  @async
   @TaskQueue(type: TaskQueueType.serialBackgroundThread)
   List<String> getAssetIdsForAlbum(String albumId);
 
+  @async
   @TaskQueue(type: TaskQueueType.serialBackgroundThread)
   List<PlatformAlbum> getAlbums();
 
+  @async
   @TaskQueue(type: TaskQueueType.serialBackgroundThread)
   int getAssetsCountSince(String albumId, int timestamp);
 
+  @async
   @TaskQueue(type: TaskQueueType.serialBackgroundThread)
   List<PlatformAsset> getAssetsForAlbum(String albumId, {int? updatedTimeCond});