git checkout <head_ref> aborted on the untracked install_steps-provided compose.host-ports.yml (which head_ref tracks). Force-checkout yields the exact ref tree. Also fixes the mumble restore tier: backup labels exist only in 1.0.0+, so backup/restore are meaningful only after the (now-working) upgrade moves the app to head_ref. DECISIONS.md updated. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>