fix(cli): reject a SECRET that cannot be saved to .env and read back unchanged - #1091

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: amannn/action-semantic-pull-request@v5.5.3. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/