docs: sync from backend 1757f1e - postgres cutover stores

08 - Operations/Monitoring.md

@@ -14,7 +14,7 @@ What's instrumented today and what to watch. Today's stack is intentionally lean
 Two paths are registered (both are public, rate-limited, not auth-gated):
 
 - `GET /health` — simple ping used by Docker healthchecks. Returns `200 { success, message, timestamp, environment, version }`. Does **not** probe MongoDB or Redis.
-- `GET /api/health` — deep health check added in commit `44579d6` (backend v2.6.49). Calls `runHealthChecks` from `backend/src/services/health/healthCheckService.ts`. Probes MongoDB, Redis, Request Network registry data, and Request Network API reachability. Returns `503` only when `report.status === 'down'`. As of backend `2.6.84`, the RN API subcheck is cached for 60 seconds and treats non-5xx HTTP responses, including `429`, as upstream reachable so Gatus/perf probes do not turn a live backend into `degraded`.
+- `GET /api/health` — deep health check added in commit `44579d6` (backend v2.6.49). Calls `runHealthChecks` from `backend/src/services/health/healthCheckService.ts`. Probes MongoDB, Postgres, Redis, Request Network registry data, and Request Network API reachability. Returns `503` only when `report.status === 'down'`. As of backend `2.8.9`, Postgres is a hard dependency only when at least one `*_STORE=postgres` flag is enabled; otherwise an unconfigured Postgres check is reported as skipped.
 
 `GET /api/health` response shape (from `healthCheckService`):
 ```json
@@ -24,6 +24,14 @@ Two paths are registered (both are public, rate-limited, not auth-gated):
   "timestamp": "...",
   "checks": {
     "db": { "ok": true, "latencyMs": 4 },
+    "postgres": {
+      "ok": true,
+      "latencyMs": 5,
+      "configured": true,
+      "required": true,
+      "database": "amanat_dev",
+      "user": "amanat"
+    },
     "redis": { "ok": true, "latencyMs": 1 },
     "rnChainRegistry": { "ok": true, "latencyMs": 0, "chainCount": 7 },
     "rnTokenRegistry": { "ok": true, "latencyMs": 0, "tokenCount": 12 },