Restores items removed with POST /videos/partial_deletion before they are permanently deleted: the quality is offered by the player again and returns to available_resolutions, the backup is available for download again, and both count toward storage again.

• Send the qualities and/or backup: true to restore only those items, or only video_id to restore everything pending for the video.
• One video per request.
• Restoring is only possible until expires_at. While the deletion is running (status: PROCESSING) it cannot be restored, and after the files are deleted there is nothing to restore.
• The remaining items keep their original deadline.