fix(cloudflared): auditable Service+ServiceMonitor scrape; placeholder-only template value

servicemonitor-ports-resolve could not audit a PodMonitor with no in-repo
Service, and no-plaintext-secrets requires a template's secret value to be a
bare placeholder.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

platform/cloudflared/servicemonitor.yaml

@@ -0,0 +1,45 @@
+---
+# Scrape of cloudflared's own metrics server (:2000, `metrics:` in config.yaml) on every replica.
+#
+# A Service + ServiceMonitor in ONE file rather than a PodMonitor, on purpose: the repo's L0 checks
+# (servicemonitor-ports-resolve, alert-metrics-have-scrape-targets assertion 4) can then prove the
+# monitor's port is a port this Service actually defines. A PodMonitor would have to be declared as
+# an unauditable exception. The Service is headless and carries only the metrics port — it is not a
+# way into the tunnel, and nothing routes to it but Prometheus (networkpolicy.yaml admits only the
+# monitoring namespace on :2000).
+#
+# kube-prometheus-stack runs with serviceMonitorSelectorNilUsesHelmValues: false, so this is
+# selected from any namespace; the `release` label is kept for consistency.
+apiVersion: v1
+kind: Service
+metadata:
+  name: cloudflared-metrics
+  namespace: cloudflared
+  labels:
+    app.kubernetes.io/name: cloudflared
+spec:
+  clusterIP: None
+  selector:
+    app.kubernetes.io/name: cloudflared
+  ports:
+    - name: metrics
+      port: 2000
+      targetPort: metrics
+      protocol: TCP
+---
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: cloudflared
+  namespace: cloudflared
+  labels:
+    app.kubernetes.io/name: cloudflared
+    release: kube-prometheus-stack
+spec:
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: cloudflared
+  endpoints:
+    - port: metrics
+      path: /metrics
+      interval: 30s