initial

src/main/java/aplp/backend/core/common/exception/ResourceNotFoundException.java

@@ -0,0 +1,8 @@
+package aplp.backend.core.common.exception;
+
+public class ResourceNotFoundException extends RuntimeException {
+
+    public ResourceNotFoundException(String message) {
+        super(message);
+    }
+}

src/main/java/aplp/backend/core/common/response/ErrorResponse.java

@@ -0,0 +1,10 @@
+package aplp.backend.core.common.response;
+
+import java.time.LocalDateTime;
+
+public record ErrorResponse(
+        int status,
+        String message,
+        LocalDateTime timestamp
+) {
+}