services/backup_s3.py is FabledSteward's SigV4 client ported (put + list,
never delete, so an append-only key is enough), with its tests against
AWS's published signatures. services/backup_destination.py holds the
admin config (backup_config JSON) and delivers a dated tar to a mounted
folder or a bucket, and checks either without sending a backup.
services/secrets.py seals the S3 secret with Fernet under a key derived
from SECRET_KEY; backup._SETTINGS_NOT_EXPORTED keeps it out of every
backup. cryptography becomes a direct dependency (already in the image
through pyjwt).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
