feat(app): clean architecture with typed repositories, DTO models and calendar event logos

FinlyticApp/lib/features/favorites/repositories/favorites_repository.dart

@@ -0,0 +1,49 @@
+import '../../../core/network/api_client.dart';
+import '../models/favorite_asset_model.dart';
+
+/// Clean Architecture Repository for managing user favorite assets.
+class FavoritesRepository {
+  final ApiClient apiClient;
+
+  const FavoritesRepository({required this.apiClient});
+
+  /// Fetches the user's favorite asset list from the backend.
+  Future<List<FavoriteAssetModel>> getFavorites() async {
+    final ts = DateTime.now().millisecondsSinceEpoch;
+    final res = await apiClient.get('/api/v1/user/favorites?_t=$ts');
+    if (res.statusCode == 200 && res.data is List) {
+      final rawList = res.data as List;
+      final dedupMap = <String, FavoriteAssetModel>{};
+
+      for (var item in rawList) {
+        if (item is Map<String, dynamic>) {
+          final model = FavoriteAssetModel.fromJson(item);
+          final key = (model.isin.isNotEmpty ? model.isin : (model.symbol.isNotEmpty ? model.symbol : model.name)).toUpperCase();
+          if (!dedupMap.containsKey(key)) {
+            dedupMap[key] = model;
+          }
+        }
+      }
+      return dedupMap.values.toList();
+    }
+    return [];
+  }
+
+  /// Adds an asset to user favorites by ISIN or symbol.
+  Future<bool> addFavorite(String identifier) async {
+    final res = await apiClient.post('/api/v1/user/favorites/$identifier');
+    return res.statusCode == 200 || res.statusCode == 201;
+  }
+
+  /// Removes an asset from user favorites.
+  Future<bool> removeFavorite(String identifier) async {
+    final res = await apiClient.delete('/api/v1/user/favorites/$identifier');
+    return res.statusCode == 200 || res.statusCode == 204;
+  }
+
+  /// Updates the preferred active ticker for a favorite asset.
+  Future<bool> updateFavoriteTicker(String symbolOrIsin, String ticker) async {
+    final res = await apiClient.post('/api/v1/user/favorites/$symbolOrIsin/ticker?ticker=$ticker');
+    return res.statusCode == 200;
+  }
+}