屏幕适配

lib/shared/widgets/app_loading_view.dart

@@ -1,22 +1,24 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_screenutil/flutter_screenutil.dart';
 
 class AppLoadingView extends StatelessWidget {
-  const AppLoadingView({super.key, this.message = '加载中', this.size = 24});
+  const AppLoadingView({super.key, this.message = '加载中', this.size});
 
   final String message;
-  final double size;
+  final double? size;
 
   @override
   Widget build(BuildContext context) {
+    final effectiveSize = size ?? 24.r;
     return Center(
       child: Column(
         mainAxisSize: MainAxisSize.min,
         children: [
           SizedBox.square(
-            dimension: size,
-            child: const CircularProgressIndicator(strokeWidth: 2.4),
+            dimension: effectiveSize,
+            child: CircularProgressIndicator(strokeWidth: 2.4.r),
           ),
-          const SizedBox(height: 12),
+          SizedBox(height: 12.h),
           Text(
             message,
             style: Theme.of(context).textTheme.bodyMedium?.copyWith(