fix: MySQL 空闲连接健康检查 + Gunicorn worker 保活，解决广播开才不卡

Co-authored-by: Cursor <cursoragent@cursor.com>

deploy/apply-lag-fix.sh

@@ -16,6 +16,14 @@ sleep 2
 systemctl is-active gunicorn-dianjing.service
 pgrep -cf 'gunicorn.*a_long_dianjing' || true
 
+echo ""
+echo ">>> 安装 worker 保活 cron（空闲后不卡）"
+chmod +x deploy/gunicorn-warmup.sh
+cp deploy/gunicorn-warmup.cron /etc/cron.d/gunicorn-warmup
+chmod 644 /etc/cron.d/gunicorn-warmup
+bash deploy/gunicorn-warmup.sh
+echo "  cron 已安装，每2分钟预热 worker"
+
 echo ""
 echo ">>> 最近慢请求 (rt>=0.5s):"
 grep -a 'hqhd' "$NGINX_LOG" | awk 'match($0,/rt=([0-9.]+)/,a){if(a[1]+0>=0.5)print}' | tail -5