ci - checkout step 이름·주석 정리

- 자신 모듈은 this branch, 의존은 master 명시
- step 이름과 주석으로 의도 가시화

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

.gitea/workflows/eapim-portal-ci.yml

@@ -23,12 +23,14 @@ jobs:
         working-directory: eapim-portal
 
     steps:
-      - name: Checkout eapim-portal (trigger SHA)
+      - name: Checkout eapim-portal (this branch)
+        # ref 미지정 — 트리거된 브랜치/commit(github.sha) 그대로 빌드.
         uses: http://172.30.1.50:3000/actions/checkout@v4
         with:
           path: eapim-portal
 
-      - name: Checkout elink-portal-common (master)
+      - name: Checkout elink-portal-common (master, dependency)
+        # 의존 모듈은 항상 master 고정.
         working-directory: ${{ github.workspace }}
         run: |
           rm -rf elink-portal-common
@@ -36,7 +38,8 @@ jobs:
             http://oauth2:${{ secrets.CI_TOKEN }}@172.30.1.50:3000/djb-eapim/elink-portal-common.git \
             elink-portal-common
 
-      - name: Checkout elink-online-core-jpa (master)
+      - name: Checkout elink-online-core-jpa (master, dependency)
+        # 의존 모듈은 항상 master 고정.
         working-directory: ${{ github.workspace }}
         run: |
           mkdir -p eapim-online