add

backend/src/main/java/com/car/common/ApiException.java

@@ -0,0 +1,13 @@
+package com.car.common;
+
+import lombok.Getter;
+
+@Getter
+public class ApiException extends RuntimeException {
+    private final int code;
+
+    public ApiException(int code, String message) {
+        super(message);
+        this.code = code;
+    }
+}