Fix deleted renter file showing up after restart
Created by: ChrisSchinnerl
When a file is deleted while being repaired, the upload of the scheduled chunks will continue. Since the upload code modifies the uploaded file's metadata, the deleted .sia
file will reappear and after a restart of sia, it will also be tracked by the renter again.
This PR fixes this by introducing a deleted
field that prevents deleted files from being saved to disk.