Sync ROADMAP statuses with landed work; mark 1.10/1.12/1.13 as paused

Tasks 1.1-1.9 marked done with their landing commit SHAs. Tasks 1.10
(observability), 1.12 (production hardening), and 1.13 (device
authority) marked paused with explicit resume triggers — pilot
deployment on real Teltonika hardware takes priority. Task 1.11
remains as next, in slimmed form for the pilot (no /readyz healthcheck
since the metrics endpoint is part of paused 1.10).

.planning/phase-1-telemetry/12-production-hardening.md

@@ -1,7 +1,7 @@
 # Task 1.12 — Production hardening
 
 **Phase:** 1 — Inbound telemetry
-**Status:** ⬜ Not started
+**Status:** ⏸ Paused — deferred until after the real-device pilot test. See ROADMAP.md "Deferred" section for resume triggers. `installGracefulShutdown` exists as a stub from task 1.8; this task fully implements signal handling, drain timeouts, unhandled-rejection handlers, and writes OPERATIONS.md. **Resume before any always-on deployment or rolling-restart workflow.**
 **Depends on:** 1.8, 1.10, 1.11
 **Wiki refs:** `docs/wiki/concepts/failure-domains.md`