This sandbox ships with no Python/Node/Docker/browser and no sudo, so the bulk of this is setup.sh: bootstrap Python via uv, then get Playwright's Chromium (and tmux, also missing) working by extracting their .deb dependencies non-root instead of apt-get install. driver.py is a small Playwright REPL standing in for chromium-cli, which isn't available here either. Also carves out .claude/skills/ from the blanket .claude/ gitignore -- skills are shared project tooling, not personal/local state.