feat: Implement ApiService with Dio for standardized API requests and responses using ApiResponse entity.

apps/mobile/packages/core/lib/core.dart

@@ -8,3 +8,4 @@ export 'src/presentation/mixins/bloc_error_handler.dart';
 export 'src/presentation/observers/core_bloc_observer.dart';
 export 'src/config/app_config.dart';
 export 'src/routing/routing.dart';
+export 'src/services/api_service.dart';

apps/mobile/packages/core/lib/src/services/api_service.dart

@@ -0,0 +1,135 @@
+import 'package:dio/dio.dart';
+import 'package:krow_domain/krow_domain.dart';
+
+/// A service that handles HTTP communication using the [Dio] client.
+///
+/// This class provides a wrapper around [Dio]'s methods to handle
+/// response parsing and error handling in a consistent way.
+class ApiService {
+  /// Creates an [ApiService] with the given [Dio] instance.
+  ApiService(this._dio);
+
+  /// The underlying [Dio] client used for network requests.
+  final Dio _dio;
+
+  /// Performs a GET request to the specified [endpoint].
+  Future<ApiResponse> get(
+    String endpoint, {
+    Map<String, dynamic>? params,
+  }) async {
+    try {
+      final Response<dynamic> response = await _dio.get<dynamic>(
+        endpoint,
+        queryParameters: params,
+      );
+      return _handleResponse(response);
+    } on DioException catch (e) {
+      return _handleError(e);
+    }
+  }
+
+  /// Performs a POST request to the specified [endpoint].
+  Future<ApiResponse> post(
+    String endpoint, {
+    dynamic data,
+    Map<String, dynamic>? params,
+  }) async {
+    try {
+      final Response<dynamic> response = await _dio.post<dynamic>(
+        endpoint,
+        data: data,
+        queryParameters: params,
+      );
+      return _handleResponse(response);
+    } on DioException catch (e) {
+      return _handleError(e);
+    }
+  }
+
+  /// Performs a PUT request to the specified [endpoint].
+  Future<ApiResponse> put(
+    String endpoint, {
+    dynamic data,
+    Map<String, dynamic>? params,
+  }) async {
+    try {
+      final Response<dynamic> response = await _dio.put<dynamic>(
+        endpoint,
+        data: data,
+        queryParameters: params,
+      );
+      return _handleResponse(response);
+    } on DioException catch (e) {
+      return _handleError(e);
+    }
+  }
+
+  /// Performs a PATCH request to the specified [endpoint].
+  Future<ApiResponse> patch(
+    String endpoint, {
+    dynamic data,
+    Map<String, dynamic>? params,
+  }) async {
+    try {
+      final Response<dynamic> response = await _dio.patch<dynamic>(
+        endpoint,
+        data: data,
+        queryParameters: params,
+      );
+      return _handleResponse(response);
+    } on DioException catch (e) {
+      return _handleError(e);
+    }
+  }
+
+  /// Extracts [ApiResponse] from a successful [Response].
+  ApiResponse _handleResponse(Response<dynamic> response) {
+    if (response.data is Map<String, dynamic>) {
+      final Map<String, dynamic> body = response.data as Map<String, dynamic>;
+      return ApiResponse(
+        code:
+            body['code']?.toString() ??
+            response.statusCode?.toString() ??
+            'unknown',
+        message: body['message']?.toString() ?? 'Success',
+        data: body['data'],
+        errors: _parseErrors(body['errors']),
+      );
+    }
+    return ApiResponse(
+      code: response.statusCode?.toString() ?? '200',
+      message: 'Success',
+      data: response.data,
+    );
+  }
+
+  /// Extracts [ApiResponse] from a [DioException].
+  ApiResponse _handleError(DioException e) {
+    if (e.response?.data is Map<String, dynamic>) {
+      final Map<String, dynamic> body =
+          e.response!.data as Map<String, dynamic>;
+      return ApiResponse(
+        code:
+            body['code']?.toString() ??
+            e.response?.statusCode?.toString() ??
+            'error',
+        message: body['message']?.toString() ?? e.message ?? 'Error occurred',
+        data: body['data'],
+        errors: _parseErrors(body['errors']),
+      );
+    }
+    return ApiResponse(
+      code: e.response?.statusCode?.toString() ?? 'error',
+      message: e.message ?? 'Unknown error',
+      errors: <String, dynamic>{'exception': e.type.toString()},
+    );
+  }
+
+  /// Helper to parse the errors map from various possible formats.
+  Map<String, dynamic> _parseErrors(dynamic errors) {
+    if (errors is Map) {
+      return Map<String, dynamic>.from(errors);
+    }
+    return const <String, dynamic>{};
+  }
+}

apps/mobile/packages/core/pubspec.yaml

@@ -21,3 +21,4 @@ dependencies:
   flutter_bloc: ^8.1.0
   equatable: ^2.0.8
   flutter_modular: ^6.4.1
+  dio: ^5.9.1

apps/mobile/packages/domain/lib/krow_domain.dart

@@ -6,6 +6,9 @@
 /// Note: Repository Interfaces are now located in their respective Feature packages.
 library;
 
+// Core
+export 'src/entities/core/services/api_service/api_response.dart';
+
 // Users & Membership
 export 'src/entities/users/user.dart';
 export 'src/entities/users/staff.dart';

apps/mobile/packages/domain/lib/src/entities/core/services/api_service/api_response.dart

@@ -0,0 +1,22 @@
+/// Represents a standardized response from the API.
+class ApiResponse {
+  /// Creates an [ApiResponse].
+  const ApiResponse({
+    required this.code,
+    required this.message,
+    this.data,
+    this.errors = const <String, dynamic>{},
+  });
+
+  /// The response code (e.g., '200', '404', or custom error code).
+  final String code;
+
+  /// A descriptive message about the response.
+  final String message;
+
+  /// The payload returned by the API.
+  final dynamic data;
+
+  /// A map of field-specific error messages, if any.
+  final Map<String, dynamic?> errors;
+}