Rollback to a previous deployment

Re-deploy the model from a previous deployment record.

The rolled-back deployment may be either a training-job deployment or a base-model deployment; this endpoint handles both shapes by mirroring whichever target was set on the source record.

Args: project_id: Project to roll back. deployment_id: Deployment record whose target will be re-activated. auth: Authenticated user.

Returns: DeploymentResponse for the new rollback deployment record.

Raises: HTTPException: 400 if the historical deployment targets a base model that is no longer in the catalog; 403 if the user does not have access to the project; 404 if the deployment record is not found for this project; 409 if the historical training job is no longer deployable.