feat: improve admin responsive pages and teacher candidates

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

@@ -10,6 +10,7 @@ import dayjs from 'dayjs';
 import api from '../../api';
 import PermissionButton from '../../components/PermissionButton';
 import { message } from '../../ui/app-message';
+import { buildTeacherCandidateOptions, type TeacherCandidateUser } from './teacher-candidate';
 
 // ---- Types ----
 
@@ -84,10 +85,7 @@ interface StudentItem {
   studentNo?: string;
 }
 
-interface UserItem {
-  id: number;
-  username: string;
-}
+type UserItem = TeacherCandidateUser;
 
 // ---- Constants ----
 
@@ -595,16 +593,13 @@ const ClassDetailPage: React.FC = () => {
                   <Space direction="vertical" style={{ width: '100%' }}>
                     <Select
                       style={{ width: '100%' }}
-                      placeholder="选择教师"
+                      showSearch
+                      optionFilterProp="label"
+                      placeholder="搜索姓名、用户名、角色或学科"
                       value={teacherUserId}
                       onChange={setTeacherUserId}
-                      options={allUsers.map((u) => ({
-                        value: u.id,
-                        label: u.username,
-                      }))}
-                      filterOption={(input, option) =>
-                        (option?.label as string)?.toLowerCase().includes(input.toLowerCase())
-                      }
+                      options={buildTeacherCandidateOptions(allUsers)}
+                      notFoundContent="没有可分配的工作人员账号"
                     />
                     <Select
                       style={{ width: '100%' }}