還原到 commonLabels,因為: 1. Deployment selector 是 immutable,不能移除 environment/system labels 2. commonLabels 只影響 spec.podSelector,不影響 egress[].to[].podSelector 3. DNS 規則 (k8s-app=kube-dns) 不會被 commonLabels 破壞 DNS 問題的根因是之前的錯誤配置,NetworkPolicy YAML 已修復 Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>