Rollback removed the live skill directory before restoring its
snapshot. When copytree then failed (disk full, locked file, path too
long on Windows) the except only added a note, and the finally deleted
the snapshot directory too, so nothing survived: the skill was gone
with a success-shaped error payload.
The broken state is now renamed aside first and deleted only after the
snapshot is restored. If the restore still fails, the broken state is
renamed back, so the worst outcome is the half applied batch instead of
no skill at all. When rollback reports any failure the snapshots are
kept on disk and their location is logged, instead of being deleted by
the finally.
Follow-up to #97692, same batch executor.
Adolanium
1315e65a52