feat(stream-density)!: judge pass/fail using time-weighted FPS - #254

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@1e31de5234b9f8995739874a8ce0492dc87873e2. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/