feat(flutter): 增加目录加载诊断与前台重试

lib/pages/home/home_view.dart

@@ -2,15 +2,20 @@
 
 import 'dart:async';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:provider/provider.dart';
 
+import '../../core/config/app_config.dart';
 import '../../core/data/models/drama.dart';
 import '../../core/data/services/catalog_controller.dart';
+import '../../core/data/services/catalog_retry.dart';
+import '../../core/data/services/category_controller.dart';
 import '../../core/platform/haptics.dart';
 import '../../core/theme/app_theme.dart';
 import '../../core/widgets/app_bottom_nav.dart';
+import '../../core/widgets/catalog_debug_info.dart';
 import '../../core/widgets/empty_state.dart';
 import '../../l10n/app_localizations.dart';
 import '../discover/discover_types.dart';
@@ -23,9 +28,57 @@ import '../mine/mine_view.dart';
 import 'home_binding.dart';
 import 'home_logic.dart';
 
-class HomePage extends StatelessWidget {
+class HomePage extends StatefulWidget {
   const HomePage({super.key});
 
+  @override
+  State<HomePage> createState() => _HomePageState();
+}
+
+class _HomePageState extends State<HomePage> with WidgetsBindingObserver {
+  bool _resumeRetryInFlight = false;
+
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addObserver(this);
+  }
+
+  @override
+  void dispose() {
+    WidgetsBinding.instance.removeObserver(this);
+    super.dispose();
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    if (state != AppLifecycleState.resumed || _resumeRetryInFlight) return;
+    final catalog = context.read<CatalogController>();
+    final categories = context.read<CategoryController>();
+    if (catalog.error == null && categories.error == null) return;
+    unawaited(_retryAfterResume(catalog, categories));
+  }
+
+  Future<void> _retryAfterResume(
+    CatalogController catalog,
+    CategoryController categories,
+  ) async {
+    _resumeRetryInFlight = true;
+    try {
+      await AppConfig.probeAndApplyBaseUrl();
+      await Future.wait([
+        if (catalog.error != null) catalog.load(),
+        if (categories.error != null) categories.load(),
+      ]);
+    } finally {
+      _resumeRetryInFlight = false;
+    }
+  }
+
+  Future<void> _retryHome(CatalogController catalog) {
+    return retryCatalogLoad(reload: catalog.load);
+  }
+
   @override
   Widget build(BuildContext context) {
     final catalog = context.watch<CatalogController>();
@@ -51,7 +104,10 @@ class HomePage extends StatelessWidget {
     if (catalog.error != null) {
       return Scaffold(
         backgroundColor: Colors.transparent,
-        body: HomeFailureView(onRetry: catalog.load),
+        body: HomeFailureView(
+          error: catalog.debugError ?? catalog.error,
+          onRetry: () => unawaited(_retryHome(catalog)),
+        ),
       );
     }
     if (catalog.dramas.isEmpty) {
@@ -78,8 +134,9 @@ class HomePage extends StatelessWidget {
 
 /// 首页目录加载失败与重试入口。
 class HomeFailureView extends StatelessWidget {
-  const HomeFailureView({super.key, required this.onRetry});
+  const HomeFailureView({super.key, this.error, required this.onRetry});
 
+  final String? error;
   final VoidCallback onRetry;
 
   @override
@@ -90,6 +147,7 @@ class HomeFailureView extends StatelessWidget {
       title: l10n.catalogError,
       actionLabel: l10n.retry,
       onAction: onRetry,
+      footer: kDebugMode ? CatalogDebugInfo(error: error) : null,
     );
   }
 }