use better responses

src/main/java/cc/fascinated/model/response/Response.java

@@ -0,0 +1,31 @@
+package cc.fascinated.model.response;
+
+import io.micrometer.common.lang.NonNull;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.servlet.function.EntityResponse;
+
+@Getter @AllArgsConstructor
+public class Response {
+
+    /**
+     * The status code of this error.
+     */
+    private HttpStatus status;
+
+    /**
+     * The message of this error.
+     */
+    private String message;
+
+    /**
+     * Gets this response as a {@link ResponseEntity}.
+     *
+     * @return the response entity
+     */
+    public ResponseEntity<?> toResponseEntity() {
+        return new ResponseEntity<>(this, status);
+    }
+}