Task 47b27ccb: a litestream sidecar (litestream/litestream:0.5.17) in
deploy/compose.yaml mounts the nestquest-db volume and replicates
/var/lib/nestquest/nestquest.db over SFTP to the Synology NAS
(10.60.1.50, /homes/Joshua/nestquest-backups), outside the Docker host.
deploy/litestream.yml holds no secrets: the NAS host key is pinned and
the dedicated SFTP private key is mounted read-only from the
git-ignored deploy/litestream_key. api/README.md documents what runs,
where it writes, key setup, and a high-level restore.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>