Collects staged files an earlier run was killed before cleaning up.
Separate from the store because it is a different job with a different
risk: the store decides what to write, this decides what may be deleted,
and the only thing they share is the naming scheme in `StagingPaths`.
Collects staged files an earlier run was killed before cleaning up.
Separate from the store because it is a different job with a different risk: the store decides what to write, this decides what may be deleted, and the only thing they share is the naming scheme in `StagingPaths`.