Fix port 80 already in use error

- Add port 80 usage detection with netstat and docker ps
- Stop and remove containers using port 80 before deployment
- Ensures clean port 80 for nginx service
- Prevents 'bind: address already in use' errors

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

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

.github/workflows/deploy.yml

@@ -89,7 +89,16 @@ jobs:
 
             echo "Deployed to $DEPLOY; backup saved at $BACKUP"
 
-            # 5) docker-compose 재시작
+            # 5) 포트 80 사용 중인 컨테이너 정리
+            echo "Checking port 80 usage..."
+            netstat -tlnp | grep :80 || true
+            docker ps --format "table {{.Names}}\t{{.Ports}}" | grep ":80" || true
+            
+            # 포트 80 사용하는 모든 컨테이너 정지
+            docker ps --filter "publish=80" -q | xargs -r docker stop
+            docker ps -a --filter "publish=80" -q | xargs -r docker rm
+
+            # 6) docker-compose 재시작
             cd "$DEPLOY"
             docker-compose down 2>/dev/null || true
             docker-compose up -d --build