Add stable v1 schema IDs and docs

docs/COMMAND_REFERENCE.md

@@ -308,6 +308,10 @@ staleness, total alerts with per-severity counts, last alert time, and eBPF
 monitor state. `--json` emits the same data as the dashboard `/api/status`
 endpoint, for cron/monitoring.
 
+Stable JSON contracts are documented in [SCHEMAS.md](SCHEMAS.md). Current v1
+IDs cover alert objects/snapshots, incident records/views/exports, status,
+response plans, and response audit JSONL records.
+
 Exit code:
 
 - `0`: daemon is running and the heartbeat is fresh.