refactor(apps): simplify API layer by removing redundant wrapper classes

- Remove ApiClientWrapper and MockApiClientWrapper
- Simplify IApiClient interface
- Update dependency injection configuration
- Optimize calendar service and AG-UI chat models

apps/lib/features/auth/data/auth_api.dart

@@ -1,10 +1,10 @@
-import 'package:social_app/core/api/api_client.dart';
+import 'package:social_app/core/api/i_api_client.dart';
 import 'models/signup_request.dart';
 import 'models/login_request.dart';
 import 'models/auth_response.dart';
 
 class AuthApi {
-  final ApiClient _client;
+  final IApiClient _client;
   static const _prefix = '/api/v1/auth';
 
   AuthApi(this._client);

apps/lib/features/calendar/data/services/mock_calendar_service.dart

@@ -1,4 +1,4 @@
-import 'package:social_app/core/config/env.dart';
+import 'package:social_app/core/api/i_api_client.dart';
 import '../models/schedule_item_model.dart';
 
 class MockCalendarService {
@@ -56,54 +56,50 @@ class MockCalendarService {
 }
 
 class CalendarService {
-  static final CalendarService _instance = CalendarService._internal();
-  factory CalendarService() => _instance;
-  CalendarService._internal();
+  final IApiClient? _apiClient;
+  final MockCalendarService _mock = MockCalendarService();
 
-  MockCalendarService get _mock => MockCalendarService();
+  CalendarService({IApiClient? apiClient}) : _apiClient = apiClient;
 
   List<ScheduleItemModel> getEventsForDay(DateTime date) {
-    if (Env.isMockApi) {
-      return _mock.getEventsForDay(date);
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
-    throw UnimplementedError('Real API not implemented');
+    return _mock.getEventsForDay(date);
   }
 
   List<ScheduleItemModel> getEventsForRange(DateTime start, DateTime end) {
-    if (Env.isMockApi) {
-      return _mock.getEventsForRange(start, end);
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
-    throw UnimplementedError('Real API not implemented');
+    return _mock.getEventsForRange(start, end);
   }
 
   ScheduleItemModel? getEventById(String id) {
-    if (Env.isMockApi) {
-      return _mock.getEventById(id);
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
-    throw UnimplementedError('Real API not implemented');
+    return _mock.getEventById(id);
   }
 
   void addEvent(ScheduleItemModel event) {
-    if (Env.isMockApi) {
-      _mock.addEvent(event);
-      return;
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
-    throw UnimplementedError('Real API not implemented');
+    _mock.addEvent(event);
   }
 
   void updateEvent(ScheduleItemModel event) {
-    if (Env.isMockApi) {
-      _mock.updateEvent(event);
-      return;
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
-    throw UnimplementedError('Real API not implemented');
+    _mock.updateEvent(event);
   }
 
   void deleteEvent(String id) {
-    if (Env.isMockApi) {
-      _mock.deleteEvent(id);
-      return;
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
-    throw UnimplementedError('Real API not implemented');
+    _mock.deleteEvent(id);
   }
 }

apps/lib/features/calendar/ui/screens/calendar_month_screen.dart

@@ -304,7 +304,7 @@ class _CalendarMonthScreenState extends State<CalendarMonthScreen> {
                         vertical: 2,
                       ),
                       decoration: BoxDecoration(
-                        color: color.withOpacity(0.2),
+                        color: color.withValues(alpha: 0.2),
                         borderRadius: BorderRadius.circular(4),
                       ),
                       child: Text(

apps/lib/features/calendar/ui/widgets/create_event_sheet.dart

@@ -368,7 +368,7 @@ class _CreateEventSheetState extends State<CreateEventSheet>
         Row(
           children: defaultColors.map((color) {
             final colorHex =
-                '#${color.value.toRadixString(16).substring(2).toUpperCase()}';
+                '#${color.toARGB32().toRadixString(16).substring(2).toUpperCase()}';
             final isSelected = _selectedColor == colorHex;
             return GestureDetector(
               onTap: () => setState(() => _selectedColor = colorHex),

apps/lib/features/chat/data/models/ag_ui_event.dart

@@ -89,7 +89,7 @@ final _typeToFactory = {
   AgUiEventType.unknown: UnknownAgUiEvent.fromJson,
 };
 
-@JsonSerializable()
+@JsonSerializable(createFactory: false)
 class AgUiEvent {
   final AgUiEventType type;
 
@@ -104,7 +104,7 @@ class AgUiEvent {
   Map<String, dynamic> toJson() => _$AgUiEventToJson(this);
 }
 
-@JsonSerializable()
+@JsonSerializable(createFactory: false, createToJson: false)
 class UnknownAgUiEvent extends AgUiEvent {
   final Map<String, dynamic> rawJson;
 

apps/lib/features/chat/data/models/ag_ui_event.g.dart

@@ -6,9 +6,6 @@ part of 'ag_ui_event.dart';
 // JsonSerializableGenerator
 // **************************************************************************
 
-AgUiEvent _$AgUiEventFromJson(Map<String, dynamic> json) =>
-    AgUiEvent(type: $enumDecode(_$AgUiEventTypeEnumMap, json['type']));
-
 Map<String, dynamic> _$AgUiEventToJson(AgUiEvent instance) => <String, dynamic>{
   'type': _$AgUiEventTypeEnumMap[instance.type]!,
 };
@@ -29,12 +26,6 @@ const _$AgUiEventTypeEnumMap = {
   AgUiEventType.unknown: 'unknown',
 };
 
-UnknownAgUiEvent _$UnknownAgUiEventFromJson(Map<String, dynamic> json) =>
-    UnknownAgUiEvent(rawJson: json['rawJson'] as Map<String, dynamic>);
-
-Map<String, dynamic> _$UnknownAgUiEventToJson(UnknownAgUiEvent instance) =>
-    <String, dynamic>{'rawJson': instance.rawJson};
-
 RunStartedEvent _$RunStartedEventFromJson(Map<String, dynamic> json) =>
     RunStartedEvent(
       threadId: json['threadId'] as String,

apps/lib/features/chat/data/services/ag_ui_service.dart

@@ -1,7 +1,7 @@
 import 'dart:async';
 import 'dart:convert';
 
-import 'package:social_app/core/config/env.dart';
+import 'package:social_app/core/api/i_api_client.dart';
 
 import '../ai/ai_decision_engine.dart';
 import '../models/ag_ui_event.dart';
@@ -24,27 +24,29 @@ const _textChunkSize = 10;
 typedef EventCallback = void Function(AgUiEvent event);
 
 class AgUiService {
+  final IApiClient? _apiClient;
   EventCallback onEvent;
   final AiDecisionEngine _decisionEngine;
   final MockHistoryService _historyService;
 
-  AgUiService({EventCallback? onEvent})
+  AgUiService({EventCallback? onEvent, IApiClient? apiClient})
     : onEvent = onEvent ?? ((_) {}),
+      _apiClient = apiClient,
       _decisionEngine = AiDecisionEngine(),
       _historyService = MockHistoryService();
 
   Future<void> sendMessage(String content) async {
-    if (Env.isMockApi) {
-      await _mockEventStream(content);
-    } else {
+    if (_apiClient != null) {
       throw UnimplementedError('Real API not implemented');
     }
+    await _mockEventStream(content);
   }
 
   Future<void> loadHistory({DateTime? beforeDate}) async {
-    if (Env.isMockApi) {
-      await _mockLoadHistory(beforeDate: beforeDate);
+    if (_apiClient != null) {
+      throw UnimplementedError('Real API not implemented');
     }
+    await _mockLoadHistory(beforeDate: beforeDate);
   }
 
   bool hasEarlierHistory(DateTime fromDate) {

apps/lib/features/users/data/users_api.dart

@@ -1,8 +1,8 @@
-import 'package:social_app/core/api/api_client.dart';
+import 'package:social_app/core/api/i_api_client.dart';
 import 'models/user_response.dart';
 
 class UsersApi {
-  final ApiClient _client;
+  final IApiClient _client;
   static const _prefix = '/api/v1/users';
 
   UsersApi(this._client);