perf(home): 冷启动提前拉取首页数据

lib/core/data/remote/api_client.dart

@@ -21,7 +21,7 @@ class ApiClient {
     this.tokenRefresher,
     this.onUnauthorized,
     this.deviceIdReader,
-  }) : baseUrl = baseUrl ?? AppConfig.apiBaseUrl {
+  }) : _fixedBaseUrl = baseUrl {
     _dio = Dio(
       BaseOptions(
         baseUrl: this.baseUrl,
@@ -45,9 +45,12 @@ class ApiClient {
     }
   }
 
-  final String baseUrl;
+  final String? _fixedBaseUrl;
   late final Dio _dio;
 
+  /// 当前请求使用的服务地址；未显式指定时跟随启动探测结果。
+  String get baseUrl => _fixedBaseUrl ?? AppConfig.apiBaseUrl;
+
   /// 取当前 access token（未登录返回 null）
   final String? Function()? accessTokenReader;
 
@@ -110,6 +113,7 @@ class ApiClient {
     bool retried = false,
     bool skipAuthRetry = false,
   }) async {
+    _syncBaseUrl();
     final disableAuthRetry = skipAuthRetry || tokenRefresher == null;
     try {
       final response = await _dio.request<Object?>(
@@ -150,5 +154,10 @@ class ApiClient {
     }
   }
 
+  void _syncBaseUrl() {
+    if (_fixedBaseUrl != null) return;
+    _dio.options.baseUrl = AppConfig.apiBaseUrl;
+  }
+
   void close() => _dio.close(force: true);
 }

lib/core/data/services/catalog_controller.dart

@@ -35,6 +35,7 @@ class CatalogController extends ChangeNotifier {
     debugError = null;
     notifyListeners();
     try {
+      await AppConfig.ready;
       feed = await repository.fetchHomeFeed();
     } on ApiException catch (exception) {
       error = exception.message;