refactor: remove departmentId from Class entity

apps/server/src/integration/dingtalk.service.ts

@@ -11,7 +11,6 @@ import { InjectRepository } from '@nestjs/typeorm';
 import { Repository } from 'typeorm';
 import { Department } from '../entities/department.entity';
 import { Student } from '../entities/student.entity';
-import { Class } from '../entities/class.entity';
 import { StudentDingMapping } from '../entities/student-ding-mapping.entity';
 
 // ── Types ──
@@ -189,8 +188,6 @@ export class DingTalkService {
     private readonly studentRepo: Repository<Student>,
     @InjectRepository(StudentDingMapping)
     private readonly studentDingMappingRepo: Repository<StudentDingMapping>,
-    @InjectRepository(Class)
-    private readonly classRepo: Repository<Class>,
   ) {}
 
   private get configured(): boolean {
@@ -381,26 +378,6 @@ export class DingTalkService {
     }
     await this.deptRepo.save(syncedDepts);
 
-    // ── Step 2.5: Auto-create Class for leaf departments ──
-    const parentIds = new Set(syncedDepts.map((d) => d.parentSourceId));
-    const leafDepts = syncedDepts.filter((d) => !parentIds.has(d.sourceId));
-    let classCreated = 0;
-    for (const leaf of leafDepts) {
-      const code = `DT_${leaf.sourceId}`;
-      const exists = await this.classRepo.findOne({ where: { code } });
-      if (!exists) {
-        const cls = this.classRepo.create({
-          name: leaf.name,
-          code,
-          departmentId: leaf.id,
-          classType: 'culture',
-          status: 'enrolling',
-        });
-        await this.classRepo.save(cls);
-        classCreated++;
-      }
-    }
-    if (classCreated > 0) this.logger.log(`从钉钉叶子部门自动创建 ${classCreated} 个班级`);
 
     // ── Step 3: Sync users per department ──
     let userCount = 0;