修复班级教师姓名显示

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

@@ -42,6 +42,7 @@ interface ClassStudent {
 interface ClassTeacher {
   id: number;
   userId: number;
+  name: string | null;
   username: string;
   roleType: string;
   subject: string | null;
@@ -360,7 +361,7 @@ const ClassDetailPage: React.FC = () => {
   ];
 
   const teacherColumns: ColumnsType<ClassTeacher> = [
-    { title: '姓名', dataIndex: 'username' },
+    { title: '姓名', dataIndex: 'name', render: (name: string | null) => name || '-' },
     {
       title: '角色',
       dataIndex: 'roleType',
@@ -509,7 +510,7 @@ const ClassDetailPage: React.FC = () => {
                         {detail.studentCount}/{detail.maxStudents || '-'}
                       </Descriptions.Item>
                       <Descriptions.Item label="班主任">
-                        {teachers.find((t) => t.roleType === 'head_teacher')?.username || '-'}
+                        {teachers.find((t) => t.roleType === 'head_teacher')?.name || '-'}
                       </Descriptions.Item>
                       <Descriptions.Item label="备注">{detail.notes || '-'}</Descriptions.Item>
                     </Descriptions>