refactor: 重构项目目录结构与路径引用

1.  调整工具类、平台相关代码的目录组织，将原有根目录下的工具类迁移到`data/`和`platform/`子目录
2.  统一修复全项目的文件导入路径，匹配新的目录结构
3.  新增Web端平台适配的Stub实现，包括Isolate、path_provider、platform_io等
4.  删除旧的单文件平台适配实现，替换为分平台的目录结构实现
5.  移除旧的iOS Widget入口文件，新增Widget Extension的权限配置
6.  调整部分组件的目录位置，统一widget的分类组织
7.  修复部分硬编码文本和废弃的正则表达式逻辑

lib/features/widget/presentation/widget_management_page.dart

@@ -1,11 +1,12 @@
-/// ============================================================
+/// ============================================================
 /// 闲言APP — 桌面小部件管理页面
 /// 创建时间: 2026-05-19
-/// 更新时间: 2026-05-19
+/// 更新时间: 2026-05-23
 /// 作用: 管理桌面小部件的安装、数据推送、主题和平台兼容说明
-/// 上次更新: 修复Android/鸿蒙端添加小部件无反应，改用requestPinWidget+手动指引
+/// 上次更新: 修复添加小部件假成功提示，增加失败检测和原生添加弹窗
 /// ============================================================
 
+import 'dart:async';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 
@@ -13,10 +14,10 @@ import '../../../core/theme/app_theme.dart';
 import '../../../core/theme/app_spacing.dart';
 import '../../../core/theme/app_typography.dart';
 import '../../../core/theme/app_radius.dart';
-import '../../../core/utils/platform_helper.dart';
-import '../../../shared/widgets/glass_container.dart';
-import '../../../shared/widgets/responsive_layout.dart';
-import '../../../shared/widgets/app_toast.dart';
+import '../../../core/utils/platform/platform_helper.dart';
+import '../../../shared/widgets/containers/glass_container.dart';
+import '../../../shared/widgets/adaptive/responsive_layout.dart';
+import '../../../shared/widgets/feedback/app_toast.dart';
 import '../models/widget_type.dart';
 import '../providers/widget_provider.dart' as wp;
 
@@ -179,24 +180,49 @@ class _WidgetManagementPageState extends ConsumerState<WidgetManagementPage> {
   };
 
   void _handleAddWidget(WidgetType type) async {
-    final success = await ref.read(wp.widgetProvider.notifier).requestPinWidget(type);
-    if (!success) {
+    final notifier = ref.read(wp.widgetProvider.notifier);
+    final wasInstalled = ref.read(wp.widgetProvider).installedWidgets.contains(type);
+
+    final pinSuccess = await notifier.requestPinWidget(type);
+
+    if (!pinSuccess) {
       if (!mounted) return;
       _showManualAddGuide(type);
       return;
     }
-    ref.read(wp.widgetProvider.notifier).addWidget(type);
-    AppToast.showInfo('${type.title} 已添加到桌面');
+
+    await Future<void>.delayed(const Duration(seconds: 2));
+
+    if (!mounted) return;
+    await notifier.loadInstalledWidgets();
+
+    final nowInstalled = ref.read(wp.widgetProvider).installedWidgets.contains(type);
+    if (nowInstalled && !wasInstalled) {
+      AppToast.showInfo('${type.title} 已添加到桌面');
+    } else if (!nowInstalled) {
+      _showManualAddGuide(type);
+    }
   }
 
   void _handlePinWidget(WidgetType type) async {
-    final success = await ref.read(wp.widgetProvider.notifier).requestPinWidget(type);
-    if (!success) {
+    final notifier = ref.read(wp.widgetProvider.notifier);
+    final pinSuccess = await notifier.requestPinWidget(type);
+
+    if (!pinSuccess) {
       if (!mounted) return;
       _showManualAddGuide(type);
       return;
     }
-    ref.read(wp.widgetProvider.notifier).addWidget(type);
+
+    await Future<void>.delayed(const Duration(seconds: 2));
+
+    if (!mounted) return;
+    await notifier.loadInstalledWidgets();
+
+    final nowInstalled = ref.read(wp.widgetProvider).installedWidgets.contains(type);
+    if (!nowInstalled) {
+      _showManualAddGuide(type);
+    }
   }
 
   void _showManualAddGuide(WidgetType type) {

lib/features/widget/providers/widget_provider.dart

@@ -1,4 +1,4 @@
-/// ============================================================
+/// ============================================================
 /// 闲言APP — 桌面小部件状态管理
 /// 创建时间: 2026-05-19
 /// 更新时间: 2026-05-19
@@ -10,7 +10,7 @@ import 'dart:ui';
 
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:home_widget/home_widget.dart';
-import 'package:xianyan/core/utils/platform_utils.dart' as pu;
+import 'package:xianyan/core/utils/platform/platform_utils.dart' as pu;
 
 import '../../../core/services/data/home_widget_service.dart';
 import '../../../core/utils/logger.dart';
@@ -101,6 +101,7 @@ class WidgetNotifier extends Notifier<WidgetState> {
       if (pu.isOhos) {
         try {
           const dynamic requestPin = HomeWidget.requestPinWidget;
+          // ignore: avoid_dynamic_calls
           await requestPin(
             qualifiedAndroidName: type.qualifiedAndroidName,
             androidName: type.androidProviderName,