fix: release beds/lockers in batchCheckOut

The batchCheckOut method was not releasing assigned beds and lockers
after checkout, leaving them orphaned as 'occupied'. Added the same
release pattern used in checkOut() — using runner.manager.update()
since batchCheckOut operates inside a QueryRunner transaction.

apps/server/src/integration/integration.module.ts

@@ -1,11 +1,11 @@
 import { Module } from '@nestjs/common';
 import { TypeOrmModule } from '@nestjs/typeorm';
-import { Department, User, Student, UserDingMapping } from '../entities';
+import { Department, User, Student, UserDingMapping, Class } from '../entities';
 import { DingTalkService } from './dingtalk.service';
 import { WeComService } from './wecom.service';
 
 @Module({
-  imports: [TypeOrmModule.forFeature([Department, User, Student, UserDingMapping])],
+  imports: [TypeOrmModule.forFeature([Department, User, Student, UserDingMapping, Class])],
   providers: [DingTalkService, WeComService],
   exports: [DingTalkService, WeComService],
 })