fix: E0006 Upgrade 提示按安装布局区分 + AUR 特别关照（bump 至 v2026.8.8.4、新增 mcpp-git） - #395

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