OptionalconfirmEndpoint de confirmación (si es diferente al de preparación)
OptionalonCallback de progreso (0-100)
OptionalparamsDomain params forwarded to the storage endpoint (file_path, bucket, entity_id, …).
Smart Upload injects operation: "upload" by default; pass params.operation to override.
Do not pass confirm or client_upload — the SDK owns those flags per upload phase.
Opciones para subida de archivos via endpoint