feat(teacher-bff): admin 命名空间 + 5 个 gRPC client + health probes + merge-resolvers + nextstep 文档

services/teacher-bff/src/admin/admin.module.ts

@@ -0,0 +1,11 @@
+// Admin 模块（P6 实现，president §5.1：admin-portal 复用 teacher-bff endpoint）
+import { Module } from "@nestjs/common";
+import { AdminService } from "./admin.service.js";
+import { ClientsModule } from "../clients/clients.module.js";
+
+@Module({
+  imports: [ClientsModule],
+  providers: [AdminService],
+  exports: [AdminService],
+})
+export class AdminModule {}