CHORE(prometheus): disable CPU/Memory overcommit alerts

- Disable KubeCPUOvercommit and KubeMemoryOvercommit alerts
- Cluster uses replica=2 with pod anti-affinity for HA

prometheus/helm-values.yaml

@@ -170,6 +170,10 @@ kubeStateMetrics:
 # 기본 ServiceMonitors
 defaultRules:
   create: true
+  # 비활성화할 개별 alert rule
+  disabled:
+    KubeCPUOvercommit: true
+    KubeMemoryOvercommit: true
   rules:
     alertmanager: true
     etcd: false