upload new photos in background with a service (#382)

* properly done background backup service

* new concurrency/locking management with heartbeat

fix communication erros with Kotlin plugin on start/stop service methods

better error handling for BackgroundService public methods

Add default notification message when service is running

* configurable WiFi & charging requirement for service

* use translations in background service

mobile/lib/modules/backup/models/available_album.model.dart

@@ -4,35 +4,45 @@ import 'package:photo_manager/photo_manager.dart';
 
 class AvailableAlbum {
   final AssetPathEntity albumEntity;
+  final DateTime? lastBackup;
   final Uint8List? thumbnailData;
   AvailableAlbum({
     required this.albumEntity,
+    this.lastBackup,
     this.thumbnailData,
   });
 
   AvailableAlbum copyWith({
     AssetPathEntity? albumEntity,
+    DateTime? lastBackup,
     Uint8List? thumbnailData,
   }) {
     return AvailableAlbum(
       albumEntity: albumEntity ?? this.albumEntity,
+      lastBackup: lastBackup ?? this.lastBackup,
       thumbnailData: thumbnailData ?? this.thumbnailData,
     );
   }
 
+  String get name => albumEntity.name;
+
+  int get assetCount => albumEntity.assetCount;
+
+  String get id => albumEntity.id;
+
+  bool get isAll => albumEntity.isAll;
+
   @override
   String toString() =>
-      'AvailableAlbum(albumEntity: $albumEntity, thumbnailData: $thumbnailData)';
+      'AvailableAlbum(albumEntity: $albumEntity, lastBackup: $lastBackup, thumbnailData: $thumbnailData)';
 
   @override
   bool operator ==(Object other) {
     if (identical(this, other)) return true;
 
-    return other is AvailableAlbum &&
-        other.albumEntity == albumEntity &&
-        other.thumbnailData == thumbnailData;
+    return other is AvailableAlbum && other.albumEntity == albumEntity;
   }
 
   @override
-  int get hashCode => albumEntity.hashCode ^ thumbnailData.hashCode;
+  int get hashCode => albumEntity.hashCode;
 }