统一弹窗风格：Material Design 3 规范，消除颜色不一致

- 所有 AlertDialog 替换为 ModernDialog
- ConfirmDialog/AssetDialogs 去掉 GlassPanel，统一 surfaceContainer 背景
- 按钮统一 FilledButton + TextButton
- 修复 import 路径

flutter_monisuo/lib/ui/pages/trade/trade_page.dart

@@ -1,5 +1,4 @@
 import 'package:flutter/material.dart';
-import 'package:lucide_icons_flutter/lucide_icons.dart';
 import 'package:provider/provider.dart';
 import '../../../core/theme/app_spacing.dart';
 import '../../../core/theme/app_theme_extension.dart';
@@ -9,6 +8,7 @@ import '../../../providers/market_provider.dart';
 import '../../../providers/asset_provider.dart';
 import '../../../data/services/trade_service.dart';
 import '../../components/neon_glow.dart';
+import '../../shared/modern_dialog.dart';
 import 'components/coin_selector.dart';
 import 'components/price_card.dart';
 import 'components/placeholder_card.dart';
@@ -283,30 +283,26 @@ class _TradePageState extends State<TradePage>
   }
 
   void _showResultDialog(bool success, String title, String message) {
-    showDialog(
+    final colorScheme = Theme.of(context).colorScheme;
+    ModernDialog.show(
       context: context,
-      builder: (ctx) => AlertDialog(
-        title: Row(
-          children: [
-            NeonIcon(
-              icon: success ? Icons.check_circle : Icons.error,
-              color: success
-                  ? ctx.appColors.up
-                  : Theme.of(ctx).colorScheme.error,
-              size: 24,
-            ),
-            SizedBox(width: AppSpacing.sm),
-            Text(title),
-          ],
-        ),
-        content: Text(message),
-        actions: [
-          TextButton(
-            child: const Text('確定'),
-            onPressed: () => Navigator.of(ctx).pop(),
+      titleWidget: Row(
+        children: [
+          NeonIcon(
+            icon: success ? Icons.check_circle : Icons.error,
+            color: success
+                ? context.appColors.up
+                : colorScheme.error,
+            size: 24,
           ),
+          SizedBox(width: AppSpacing.sm),
+          Text(title),
         ],
       ),
+      description: message,
+      actions: [
+        ModernDialogAction(label: '確定', isPrimary: true),
+      ],
     );
   }
 }