Kustomize 레이블 구조 최적화 완료

- Base에 system: phonebill 공통 레이블 추가
- 환경별 overlay에서 중복 labels 설정 제거
- 파일 끝 줄바꿈 정리로 일관성 확보
- 모든 환경 Kustomize 빌드 검증 완료

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

deployment/cicd/kustomize/base/kustomization.yaml

@@ -42,6 +42,9 @@ resources:
   - kos-mock/service.yaml
   - kos-mock/cm-kos-mock.yaml
 
+commonLabels:
+  system: phonebill
+
 images:
   - name: acrdigitalgarage01.azurecr.io/phonebill/api-gateway
     newTag: latest

deployment/cicd/kustomize/overlays/prod/kustomization.yaml

@@ -63,8 +63,3 @@ images:
     newTag: prod-latest
   - name: acrdigitalgarage01.azurecr.io/phonebill/kos-mock
     newTag: prod-latest
-
-labels:
-  - includeSelectors: true
-    pairs:
-      environment: prod

deployment/cicd/kustomize/overlays/staging/kustomization.yaml

@@ -63,8 +63,3 @@ images:
     newTag: staging-latest
   - name: acrdigitalgarage01.azurecr.io/phonebill/kos-mock
     newTag: staging-latest
-
-labels:
-  - includeSelectors: true
-    pairs:
-      environment: staging