feat: step 9d turns the head with depth - #44

Step 10. Browser, README line 2: shell exit 7

Step 1. Set up, README line 3: walkthrough timeout (including unclassified persistent commands)

Step 1. Set up, README line 9: shell exit 127

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, actions/upload-artifact@v4, astral-sh/setup-uv@v6. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/