C1: review CC observability-stack-audit (extend to k3s)

Recurring compensating-control review. Verified:

- alloy-k8s: Synced/Healthy on minikube-indri (DaemonSet 1/1 ready)
- alloy-ringtail: Synced/Healthy on k3s-ringtail
- loki (monitoring/loki-0): Running, receiving logs

The previous description named only minikube, but BlumeOps now runs two
clusters with the migration to ringtail in progress. Generalized the
description and notes to cover both, and added a follow-up note that
enabling native apiserver audit logging is much more tractable on k3s
than it was on minikube.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

compensating-controls.yaml

@@ -196,11 +196,15 @@ controls:
     description: >-
       Alloy collects pod logs and ships them to Loki, providing an
       audit trail for cluster activity. Compensates for missing
-      apiserver audit logging which minikube does not configure.
+      apiserver audit logging which neither minikube (indri) nor
+      k3s (ringtail) configures by default.
     created: 2026-03-30
-    last-reviewed: 2026-03-30
+    last-reviewed: 2026-05-11
     notes: >-
-      Verify Alloy DaemonSet is running and Loki is receiving logs.
+      Verify Alloy DaemonSet is running on each cluster (alloy-k8s on
+      minikube, alloy-ringtail on k3s) and Loki is receiving logs.
       Note this is weaker than native apiserver audit logs — it
       captures pod stdout/stderr, not API request-level auditing.
-      Consider enabling minikube audit logging if supported.
+      Consider enabling apiserver audit logging on k3s post-migration
+      (`--audit-log-path` / `--audit-policy-file`) — minikube made it
+      hard, k3s makes it straightforward.

docs/changelog.d/review-cc-observability-stack-audit-2026-05-11.infra.md

@@ -0,0 +1 @@
+Reviewed compensating control `observability-stack-audit`. Updated description to cover ringtail's k3s as well as indri's minikube; both Alloy DaemonSets and Loki are healthy.