snapshot purge, and the purge step of snapshot create --prune, logged a
failed local index delete, then deleted that snapshot's metadata from
the destination store anyway and exited 0, leaving a local record whose
metadata was gone. It now stops at that snapshot with an error, before
touching its metadata, so the command exits non-zero; snapshots already
purged stay purged. This matches how the same loop already handles a
failed metadata delete.
Model: opus-5-5
