feat: 为划转页面确认按钮添加图标

- 添加 LucideIcons.arrowRightLeft 图标到确认按钮
- 加载状态时自动隐藏图标
- 提升用户体验和视觉识别度

flutter_monisuo/lib/ui/pages/asset/transfer_page.dart

@@ -212,6 +212,7 @@ class _TransferPageState extends State<TransferPage> {
                   width: double.infinity,
                   child: NeonButton(
                     text: _isLoading ? '处理中...' : '确认划转',
+                    icon: _isLoading ? null : LucideIcons.arrowRightLeft,
                     type: NeonButtonType.primary,
                     onPressed: _isLoading ? null : _doTransfer,
                     height: 52,