feat(mobile): backup to album

mobile/lib/models/backup/backup_candidate.model.dart

@@ -0,0 +1,36 @@
+// ignore_for_file: public_member_api_docs, sort_constructors_first
+
+import 'package:photo_manager/photo_manager.dart';
+
+class BackupCandidate {
+  final String albumName;
+  final AssetEntity asset;
+
+  BackupCandidate({
+    required this.albumName,
+    required this.asset,
+  });
+
+  BackupCandidate copyWith({
+    String? albumName,
+    AssetEntity? asset,
+  }) {
+    return BackupCandidate(
+      albumName: albumName ?? this.albumName,
+      asset: asset ?? this.asset,
+    );
+  }
+
+  @override
+  String toString() => 'BackupCandidate(albumName: $albumName, asset: $asset)';
+
+  @override
+  bool operator ==(covariant BackupCandidate other) {
+    if (identical(this, other)) return true;
+
+    return other.albumName == albumName && other.asset == asset;
+  }
+
+  @override
+  int get hashCode => albumName.hashCode ^ asset.hashCode;
+}

mobile/lib/models/backup/backup_state.model.dart

@@ -2,7 +2,7 @@
 
 import 'package:cancellation_token_http/http.dart';
 import 'package:collection/collection.dart';
-import 'package:photo_manager/photo_manager.dart';
+import 'package:immich_mobile/models/backup/backup_candidate.model.dart';
 
 import 'package:immich_mobile/models/backup/available_album.model.dart';
 import 'package:immich_mobile/models/backup/current_upload_asset.model.dart';
@@ -41,7 +41,7 @@ class BackUpState {
   final Set<AvailableAlbum> excludedBackupAlbums;
 
   /// Assets that are not overlapping in selected backup albums and excluded backup albums
-  final Set<AssetEntity> allUniqueAssets;
+  final Set<BackupCandidate> allUniqueAssets;
 
   /// All assets from the selected albums that have been backup
   final Set<String> selectedAlbumsBackupAssetsIds;
@@ -94,7 +94,7 @@ class BackUpState {
     List<AvailableAlbum>? availableAlbums,
     Set<AvailableAlbum>? selectedBackupAlbums,
     Set<AvailableAlbum>? excludedBackupAlbums,
-    Set<AssetEntity>? allUniqueAssets,
+    Set<BackupCandidate>? allUniqueAssets,
     Set<String>? selectedAlbumsBackupAssetsIds,
     CurrentUploadAsset? currentUploadAsset,
   }) {