Prepare State Hub retirement baseline

docs/cluster-operating-model.md

@@ -159,6 +159,19 @@ Runbook: [`docs/consistency-sweep-runbook.md`](consistency-sweep-runbook.md).
 cutover while the bridge target chain was rewired. Manual sweeps succeed.
 Re-enablement is tracked outside this workplan (service-inventory gap).
 
+## Activity-core ops run visibility
+
+Ops-run claims, leases, completion, and failure remain on activity-core in
+Railiance. State Hub only exposes the cached read projection described in
+[`ops-run-read-projection.md`](ops-run-read-projection.md). Configure the
+coulombcore State Hub deployment with a private `ACTIVITY_CORE_URL` and an
+OpenBao/ESO-injected `ACTIVITY_CORE_WORKER_TOKEN`.
+
+If the Railiance edge or tunnel is unavailable, State Hub serves the last
+successful projection with `stale: true`; before any successful pull it returns
+`available: false`. Alert on those flags. Do not add claim or completion writes
+to State Hub as a failover mechanism.
+
 ## Pragmatic Limitations (Single-Node)
 
 This deployment is intentionally **not** highly available:
@@ -197,4 +210,4 @@ After image or chart changes, see `deploy/railiance/README.md` and
 - `workplans/CUST-WP-0011-state-hub-threephoenix-migration.md` — migration plan
 - `workplans/CUST-WP-0038-state-hub-threephoenix-ha.md` — future HA target
 - `deploy/railiance/README.md` — Helm/CNPG handoff
-- `the-custodian/ops/service-inventory.yml` — live endpoint inventory
+- `the-custodian/ops/service-inventory.yml` — live endpoint inventory