a181625c89
Includes: - gitea-backups/bin/backup.sh (per-push bundle + DB snapshot to local + S3) - gitea-backups/bin/install-hooks.sh (idempotent post-receive shim installer) - gitea-backups/bin/retention.sh (count-based retention: keep newest 7 dates) - gitea-mirror/bin/auto-mirror.sh (Gitea -> GitHub push mirror automation, hardened against Gitea outages) - crontab.txt (reference for the 3 cron entries) - README.md (architecture, layout, bootstrap)