task-monitor 4/6: ratatui front end (repo view + all-repos overview, real-time): the task-monitor binary in monitor/ - #282

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/