8.1 错误响应格式

{
  "success": false,
  "error": {
    "code": "INVALID_SIGNATURE",
    "message": "Signature verification failed",
    "details": "The signature does not match expected value",
    "field": "x-signature",
    "suggestion": "Please check your signature algorithm and secret key"
  },
  "requestId": "req_123456",
  "timestamp": "2024-01-01T12:00:00Z"
}