IsRunning flips before the restore goroutine parks in StopStack; under parallel
load the ==1 assertion raced it and read 0. Wait for the first stop to land, then
assert — the red-proof property (no-fast-path mutant → count 2) is preserved.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PSK5g6qYLknKj8u3QAFEr6
Re-adjudicates F4: /backup/restore, /backup/tier2/restore, /backup/offbox/restore
blocked the HTTP request until completion, so through cloudflared's 100s cap a
customer got an error page while the restore succeeded (offbox worse — bounded
on r.Context(), canceling the SFTP restore mid-flight). Convert all three to the
offboxRun async shape: fast-path IsRunning refuse, background goroutine
(offbox ctx off r.Context() -> Background+30m), instant redirect. Add mutex-
guarded op-status (opstatus.go) + GET /api/backup/restore-status + a 3s-polling
backups.html banner (neutral running, red on failure). Restore single-flight
unchanged. Tests + red-proof (sync handler blocks indefinitely vs <500ms async).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PSK5g6qYLknKj8u3QAFEr6
admin