fix: Correct documentation and deployment script issues - #179

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, cardinalby/export-env-action@66657b34899a2d695434ed060d9f2215db9b4035. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/