{"message":"🚀 服务器运行中","status":"ok","endpoints":{"GET /api/users":"获取所有用户","GET /api/users/:id":"获取单个用户","POST /api/users":"创建用户 (body: {name, email})","PUT /api/users/:id":"更新用户 (body: {name, email})","DELETE /api/users/:id":"删除用户","GET /api/health":"健康检查"}}