fix: 修复proxy_service和account_service中不当的顶层import

- proxy_service.py: 将requests和WhitelistManager改为函数内延迟import，
  避免启动时加载不需要的依赖；移除未使用的get_exit_ip_via_proxy导入
- account_service.py: 移除未使用的func、joinedload、AuditLog、
  user_has_permission顶层导入

web/frontend/src/pages/AccountsPage.tsx

@@ -3,9 +3,10 @@ import {
   Table, Button, Modal, Input, Select, message, Popconfirm, Typography, Tag, Space,
   Row, Col, Card, Statistic,
 } from 'antd';
+import type { TableProps } from 'antd';
 import { ImportOutlined, DeleteOutlined, TagOutlined, FilterOutlined } from '@ant-design/icons';
 import { accountApi, userApi, type AccountItem, type UserInfo } from '../api/modules';
-import { getUser, hasPerm } from '../store/auth';
+import { usePermissions } from '../hooks/usePermissions';
 import { getErrorMessage } from '../utils/error';
 
 const { TextArea } = Input;
@@ -27,12 +28,12 @@ export default function AccountsPage() {
   const [selectedRowKeys, setSelectedRowKeys] = useState<React.Key[]>([]);
   const [batchTagInput, setBatchTagInput] = useState('');
   const [batchTagVisible, setBatchTagVisible] = useState(false);
-  const user = getUser();
+  const { can } = usePermissions();
 
-  const canViewAll = hasPerm(user, 'account:view_all');
-  const canImport = hasPerm(user, 'account:import');
-  const canAssign = hasPerm(user, 'account:assign');
-  const canDelete = hasPerm(user, 'account:delete');
+  const canViewAll = can('account:view_all');
+  const canImport = can('account:import');
+  const canAssign = can('account:assign');
+  const canDelete = can('account:delete');
 
   const loadAccounts = async () => {
     setLoading(true);
@@ -52,14 +53,18 @@ export default function AccountsPage() {
     try {
       const data = await userApi.list();
       setUsers(data.filter((u) => u.role === 'support'));
-    } catch {}
+    } catch {
+      // 忽略客服列表加载失败，账号列表仍可继续使用。
+    }
   };
 
   const loadTags = async () => {
     try {
       const data = await accountApi.listTags();
       setTags(data);
-    } catch {}
+    } catch {
+      // 忽略标签加载失败，页面会退化为无标签筛选。
+    }
   };
 
   useEffect(() => {
@@ -167,7 +172,7 @@ export default function AccountsPage() {
     }
   };
 
-  const columns = [
+  const columns: TableProps<AccountItem>['columns'] = [
     { title: 'ID', dataIndex: 'id', width: 60 },
     { title: '用户名', dataIndex: 'username' },
     {