test(#167): watcher 那条把定长 sleep 换成轮询 —— 4.0s sleep 装在 5.0s 预算里,CI 实测已红一次 - #931

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/