errors.go
func ErrMissingRequiredField(field string) error {
	return ErrorResponse{
		Code:    http.StatusBadRequest,
		Message: fmt.Sprintf("missing required field: %s", field),
	}
}
func ErrMissingRequiredField(field string) error {
	return ErrorResponse{
		Code:    http.StatusBadRequest,
		Message: fmt.Sprintf("missing required field: %s", field),
	}
}
// ErrMissingRequiredField indicates the request
// is missing a required field.