Implement AUDIT-WP-0006 honest operational custody.

Postgres now reports custody_class=operational with a cited 30-day
recoverable window. Join ITC-CAP operations.audit at D4, publish the
interface card, and overlay user-engine tenants [*] from Git so an
ExternalSecret refresh cannot shrink it.

registry/indexes/capabilities.yaml

@@ -1,14 +1,16 @@
 version: 1
-updated: '2026-06-16'
-domain: helix_forge
+updated: '2026-08-16'
+domain: infotech
 capabilities:
 - id: capability.audit.event-retain
   name: Audit Event Retention
   summary: Collect, normalize, retain, and search audit events with integrity evidence
     across tenants.
-  vector: D4 / A2 / C2 / R1
-  domain: helix_forge
-  status: draft
+  joins: operations.audit
+  provision: data/capability/audit-core-operational.json
+  vector: D4 provision / A4 / C3 / R2
+  domain: infotech
+  status: production
   owner: audit-core
   path: registry/capabilities/capability.audit.event-retain.md
   tags:
@@ -16,4 +18,5 @@ capabilities:
   - retention
   - compliance
   consumption_modes:
+  - http ingest
   - source module