Cleanup Failed Backups

This role installs and runs the cleanback CLI to validate and delete failed Docker backups under /Backups/*/backup-docker-to-local.
Validation is performed via dirval; failures can be removed automatically in a non-interactive service execution.

Behavior

• Installs cleanback via pkgmgr.

• Runs cleanback (main.py) as a systemd oneshot service.

• Executes --all with --yes so failing directories are deleted automatically.

• No defaults for runtime knobs:

  • CLEANBACK_TIMEOUT_SECONDS (required)

  • SYS_SCHEDULE_CLEANUP_FAILED_BACKUPS (required)

• Workers (CLEANUP_FAILED_BACKUPS_WORKERS) are derived from Ansible facts only (no arbitrary defaults). Facts must be gathered.