feat: add exam score management

apps/server/src/rbac/rbac.service.ts

@@ -26,6 +26,7 @@ const PRESET_PERMISSIONS: Array<{ code: string; name: string; group: string }> =
   { code: 'student:delete', name: '归档学生', group: 'student' },
   { code: 'student:import', name: '导入学生', group: 'student' },
   { code: 'student:export', name: '导出学生', group: 'student' },
+  { code: 'exam:view', name: '查看和录入考试成绩', group: 'exam' },
   { code: 'room:view', name: '查看宿舍', group: 'room' },
   { code: 'room:create', name: '新增宿舍', group: 'room' },
   { code: 'room:edit', name: '编辑宿舍', group: 'room' },
@@ -203,6 +204,7 @@ export const PRESET_ROLES: Array<{
     isSystem: true,
     permissionGroups: [
       'student',
+      'exam',
       'class',
       'schedule',
       'attendance',