feat: implement zero-downtime Green/Blue deployment using local TCP proxy

.gitea/workflows/deploy.yml

@@ -100,6 +100,7 @@ jobs:
 
       - name: Package artifact
         run: |
+          cp deploy_gb.sh ./publish/deploy_gb.sh
           tar -czf taxbaik_deploy.tgz -C ./publish .
           echo "✓ Package: $(du -sh taxbaik_deploy.tgz | cut -f1)"
 
@@ -163,11 +164,9 @@ jobs:
           test -s "\$DEPLOY_DIR/appsettings.Production.json" \
             || { echo "FATAL: appsettings.Production.json 없음" >&2; exit 1; }
 
-          echo "--- [3/5] 심볼릭 링크 전환 ---"
-          ln -sfn "\$DEPLOY_DIR" "\$DEPLOY_HOME/taxbaik_active"
-
-          echo "--- [4/5] 서비스 재시작 ---"
-          sudo /usr/bin/systemctl restart taxbaik
+          echo "--- [3/4] Green-Blue 배포 실행 ---"
+          chmod +x "\$DEPLOY_DIR/deploy_gb.sh"
+          "\$DEPLOY_DIR/deploy_gb.sh" "\$DEPLOY_DIR"
 
           echo "--- [5/5] 헬스 체크 (최대 60초) ---"
           ATTEMPTS=20