Raw CFDI/PAC error body produced by handleCFDIError. Not the standardized
envelope. On POST /v2/invoices/income, /egress and /invoices/draft/{id}/stamp
this object is nested one level deeper, under a message key
({ "message": { "error": …, "code": …, "retryable": … } }); on
DELETE /v2/invoices/{id} it is returned at the top level.
{
"error": "Error al timbrar la factura: El CSD del emisor no es válido.",
"code": "csd_validation_error",
"providerMessage": "CFDI40147 - El campo UsoCFDI no es válido",
"retryable": false
}