refactor：重构核心模块架构

- 重构用户管理服务，优化内存服务实现
- 简化zulip_core模块结构，移除冗余配置和接口
- 更新用户状态枚举和实体定义
- 优化登录核心服务的测试覆盖

src/core/db/users/users.integration.spec.ts

@@ -25,7 +25,7 @@ import { UsersService } from './users.service';
 import { UsersMemoryService } from './users_memory.service';
 import { Users } from './users.entity';
 import { CreateUserDto } from './users.dto';
-import { UserStatus } from '../../../business/user_mgmt/user_status.enum';
+import { UserStatus } from './user_status.enum';
 
 describe('Users Module Integration Tests', () => {
   let databaseModule: TestingModule;