If a restic process dies mid-operation (e.g. the SFTP connection drops)
it leaves a lock in the repo that blocks every later forget --prune and
check until it is manually removed.
When a restic command exits with code 11 (failed to lock repository),
both scripts now run a plain `restic unlock` and retry once. Without
--remove-all, restic only removes locks from dead processes on this
host or locks not refreshed in 30 minutes, so locks held by running
operations are never removed.
The integrity check now reports a lock conflict as "could not run"
instead of claiming the repository may be corrupted, and the
connectivity checks use --no-lock.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>