TA 역할 Spring 경계 smoke (role-ta-live-1522-001)

src/main/java/com/runtimematrix/controller/dto/ErrorResponse.java

@@ -0,0 +1,14 @@
+package com.runtimematrix.controller.dto;
+
+import java.time.Instant;
+
+/** RFC 7807 Problem Details 형식의 오류 응답 DTO */
+public record ErrorResponse(
+    String type, String title, int status, String detail,
+    String instance, String timestamp, String traceId
+) {
+    public static ErrorResponse of(String type, String title, String detail,
+            int status, String instance, String traceId) {
+        return new ErrorResponse(type, title, status, detail, instance, Instant.now().toString(), traceId);
+    }
+}