chore: add documentation comments and stylecop rules

src/Api/TakeoutSaaS.UserApi/Controllers/HealthController.cs

@@ -23,7 +23,10 @@ public class HealthController : BaseApiController
     [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status200OK)]
     public ApiResponse<object> Get()
     {
+        // 1. 构造健康状态
         var payload = new { status = "OK", service = "UserApi", time = DateTime.UtcNow };
+
+        // 2. 返回健康响应
         return ApiResponse<object>.Ok(payload);
     }
 }