feat(admin): 用户体验体系化提升与高危缺陷修复

UX 缺陷修复:
- 校验失败不再卡死弹窗按钮(Users/Roles/Bills)
- 押金收取/批量收取/添加分期防重复提交;切换房型重置勾选
- AI 表单/批量确认不再出现"假成功"
- Dashboard 各数据模块独立加载,单接口失败不再整页清零
- 房间可视化加载失败显示错误态而非永久转圈
- 学生编辑表单回填前重置,避免字段残留污染
- 覆盖式导入增加二次确认;恢复默认考勤时段确认并同步表单
- 金数据匹配关闭前确认,同步中禁止误关

体验提升:
- 新增统一 QueryErrorState/QueryEmpty,20+ 页面加载失败显示错误态与重试
- 全局 ErrorBoundary + RouteKeeper 逐页兜底
- 新增 usePageVisible/useVisibleRefetch,保活页面切回自动刷新数据
- 新增首次登录角色引导 RoleTour 与业务闭环 NextStepHint 引导卡
- 重构 A2UI:useSubmissionState/useXCardSurface 收敛状态与命令生命周期,
  ArtifactErrorBoundary 渲染降级,图表空数据占位
- AI 助手欢迎语与建议话术按角色定制,会话列表空态引导
- 更新 a2ui-contract.md 契约文档说明实现现状

apps/admin/src/pages/Classes/index.tsx

@@ -30,6 +30,8 @@ import PermissionButton from '../../components/PermissionButton';
 import EditableCell from '../../components/EditableCell';
 import { message } from '../../ui/app-message';
 import { usePermission } from '../../hooks/usePermission';
+import { QueryErrorState } from '../../components/QueryState';
+import { useVisibleRefetch } from '../../hooks/usePageVisible';
 
 interface ClassItem {
   id: number;
@@ -93,25 +95,24 @@ const ClassesPage: React.FC = () => {
     data = [],
     isLoading,
     isFetching,
+    isError,
+    refetch,
   } = useQuery<ClassItem[]>({
     queryKey: ['classes', filterStatus, filterType, showArchived],
     queryFn: async () => {
-      try {
-        const params: Record<string, string | boolean | undefined> = {};
-        if (filterStatus) params.status = filterStatus;
-        if (filterType) params.classType = filterType;
-        params.isArchived = showArchived;
-        return validateResponse<ClassItem[]>(
-          classesSchema,
-          await api.get<ClassItem[]>('/classes', { params } as Record<string, unknown>),
-        );
-      } catch (e: any) {
-        message.error(e?.message || '加载失败，请稍后重试');
-        return [];
-      }
+      const params: Record<string, string | boolean | undefined> = {};
+      if (filterStatus) params.status = filterStatus;
+      if (filterType) params.classType = filterType;
+      params.isArchived = showArchived;
+      return validateResponse<ClassItem[]>(
+        classesSchema,
+        await api.get<ClassItem[]>('/classes', { params } as Record<string, unknown>),
+      );
     },
   });
   const loading = isLoading || isFetching;
+  // RouteKeeper 保活页面切回时刷新列表，避免看到陈旧数据
+  useVisibleRefetch(['classes']);
 
   const saveMutation = useApiMutation(
     async (payload: Record<string, unknown>) =>
@@ -430,19 +431,27 @@ const ClassesPage: React.FC = () => {
           />
         </span>
       </Space>
-      <Table<ClassItem>
-        columns={columns}
-        dataSource={filtered}
-        rowKey="id"
-        loading={loading}
-        locale={{ emptyText: <Empty description="暂无数据" /> }}
-        pagination={{
-          defaultPageSize: 20,
-          showSizeChanger: true,
-          pageSizeOptions: [20, 50, 100],
-        }}
-        scroll={{ x: 1100 }}
-      />
+      {isError ? (
+        <QueryErrorState
+          title="班级数据加载失败"
+          description="请检查网络后重试。"
+          onRetry={() => void refetch()}
+        />
+      ) : (
+        <Table<ClassItem>
+          columns={columns}
+          dataSource={filtered}
+          rowKey="id"
+          loading={loading}
+          locale={{ emptyText: <Empty description="暂无数据" /> }}
+          pagination={{
+            defaultPageSize: 20,
+            showSizeChanger: true,
+            pageSizeOptions: [20, 50, 100],
+          }}
+          scroll={{ x: 1100 }}
+        />
+      )}
 
       <Modal
         title={editing ? '编辑班级' : '创建班级'}