Delete and expiry for temporary jobs

Upload-backed input and output files are temporary artifacts tied to a job. They are not meant to be a persistent file library, project history, or account storage.

When a tool offers delete controls, use them after downloading the result. Deleting a completed job should remove the temporary artifacts associated with that job from the active workflow.

Browser restore features should store only job references such as a job id, not raw uploaded file content. If a job expires or is deleted, restore cannot recreate the original file.

Manual ad slots stay disabled during approval review, and ad placement should stay away from upload zones, primary controls, result controls, downloads, and delete actions.