feat: adopt security zones and explicit workload refs

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a0291a-1e87-7151-9934-fcbfe3f65eb1

tenancy.yaml

@@ -8,6 +8,17 @@ framework: netkingdom-tenancy-posture
 service: ops-warden
 role: ssh-certificate-authority
 
+workload_identity:
+  name: ops-warden
+  kind: operational-control-plane
+  responsible_repo: ops-warden
+  identity_bindings:
+    - scheme: kubernetes-service-account
+      authority: railiance01
+      subject: system:serviceaccount:ops-warden:ops-warden
+      principal_type: service
+      environment: prod
+
 tenancy:
   current:
     I: 1
@@ -108,13 +119,25 @@ tenancy:
       is single-node with a shared control plane, and under Decision 4.6.1 that
       caps V for everything bound to it (see NK-WP-0027).
 
-# zones: (reserved, tenancy-posture_v0.1 Decision 5.6)
-#
-# Deliberately absent. The security-zone standard is being drafted by
-# zone-engine (ZONE-WP-0001) and no zone vocabulary exists yet, so any value
-# here would be fabricated — the failure §6 exists to prevent. ops-warden is
-# the first intended consumer and will populate this key once the sibling
-# standard defines it (WARDEN-WP-0032-T03).
+zones:
+  standard: security-zones_v0.1
+  membership: z1-operational
+  responsible_party: team:platform-security
+  justification: >-
+    The attended platform signing service has a bounded operational scope and
+    internal metadata exposure. It has M1 evidence, but no SLO history, on-call
+    rotation, or incident exercise that would support z2-protected.
+  context:
+    maturity: M1
+    criticality: medium
+    data_classification: internal
+  evidence:
+    - ref: docs/evidence/security-zone-admission-2026-08-22.md
+      supports: [M1, platform-only-scope, basic-slo, data-handling-note]
+    - ref: history/2026-08-19-flex-auth-caller-identity-evidence.md
+      supports: [production-policy-path, authenticated-caller]
+  reviewed: "2026-08-22"
+  review_due: "2026-11-22"
 
 evidence:
   A: >-