docs(qa): 2026-W19 周报不是合法 UTF-8(已绊倒两个扫描脚本),修成可读并标出截断处 - #858

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/