find -maxdepth 3 couldn't reach immich's thumbs/<uuid>/XX/YY/file (4
levels deep), so it exhausted the 256x256 hash-bucket fan-out with no
match and timed out on every run -- 3 spurious remounts/restarts of
immich_server within 15 minutes of deploy, all falsely alerted as
staleness. Drop -maxdepth entirely; -quit already stops at the first
match via depth-first search, so it's fast regardless of tree depth.
Stale NFS handles inside containers (ESTALE/errno -116) can persist even
after the host-side mount looks healthy, requiring a manual remount +
container restart. Adds systemd mount-ready hooks (BindsTo) to restart
immich_server/calibre/ocis when their NFS mount unit restarts, plus a
5-minute health-check timer that does a real nested read and force-remounts
on staleness. Host files backed up under system-config/nfs-self-heal/ so
they can be reinstalled after a host rebuild.