Selkies 2.0 base + official WeChat + Alpha 0.2.0 + proot-apps evaluation / 迁移到 Selkies 2.0，集成官方微信与 Alpha - #1

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, actions/setup-python@v5. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/