修正

backend/app/core/exceptions.py

@@ -0,0 +1,11 @@
+from fastapi import HTTPException
+
+class BusinessException(HTTPException):
+    def __init__(self, error_code: str, message: str):
+        super().__init__(
+            status_code=400,
+            detail={
+                "error_code": error_code,
+                "message": message
+            }
+        )