feat(App): update Finlytic Flutter app UI and blocs

FinlyticApp/lib/features/auth/repositories/auth_repository.dart

@@ -0,0 +1,78 @@
+import 'package:finlytic_app/core/network/api_client.dart';
+import 'package:finlytic_app/core/services/secure_storage_service.dart';
+import 'package:finlytic_app/features/auth/models/user_model.dart';
+
+class AuthRepository {
+  final ApiClient apiClient;
+  final SecureStorageService storageService;
+
+  AuthRepository({
+    required this.apiClient,
+    required this.storageService,
+  });
+
+  Future<UserModel?> checkAuthStatus() async {
+    final token = await storageService.getToken();
+    if (token == null || token.isEmpty) {
+      return null;
+    }
+    try {
+      final response = await apiClient.get('/api/v1/user/me');
+      if (response.statusCode == 200 && response.data != null) {
+        return UserModel.fromJson(response.data, token: token);
+      } else {
+        await storageService.clearAll();
+        return null;
+      }
+    } catch (_) {
+      await storageService.clearAll();
+      return null;
+    }
+  }
+
+  Future<UserModel> login(String email, String password) async {
+    final res = await apiClient.post('/api/v1/auth/login', data: {
+      'email': email,
+      'password': password,
+    });
+    if (res.statusCode == 200 && res.data != null) {
+      if (res.data['requiresPasswordChange'] == true) {
+        throw RequiresPasswordChangeException(res.data['userId']?.toString() ?? '');
+      }
+
+      final token = res.data['token']?.toString() ?? '';
+      final user = UserModel.fromJson(res.data, token: token);
+      await storageService.saveToken(token);
+      await storageService.saveUserEmail(user.email);
+      return user;
+    } else {
+      throw Exception('Ungültige Anmeldedaten');
+    }
+  }
+
+  Future<UserModel> register(String email, String password, String fullName) async {
+    final res = await apiClient.post('/api/v1/auth/register', data: {
+      'email': email,
+      'password': password,
+      'fullName': fullName,
+    });
+    if (res.statusCode == 200 && res.data != null) {
+      final token = res.data['token']?.toString() ?? '';
+      final user = UserModel.fromJson(res.data, token: token);
+      await storageService.saveToken(token);
+      await storageService.saveUserEmail(user.email);
+      return user;
+    } else {
+      throw Exception('Registrierung fehlgeschlagen');
+    }
+  }
+
+  Future<void> logout() async {
+    await storageService.clearAll();
+  }
+}
+
+class RequiresPasswordChangeException implements Exception {
+  final String userId;
+  RequiresPasswordChangeException(this.userId);
+}