`[2026-09-21]` Backup alarm verdict split: `STALE` (exit 1) vs `ERRORED-JOBS` (exit 3)

Backup alarm verdict split: STALE (exit 1) vs ERRORED-JOBS (exit 3) (7fe4102). It had been printing STALE over 37 FRESH layers and zero stale ones — a false statement of fact, flagged by infra-hermes. STALE is a claim about backup AGE; a job that ran and errored is a different claim with different urgency. Wrapper mirrors the code and sends 🟡 not 🔴.