- Replace setup.py with pyproject.toml using uv_build backend
- Add dependency-groups.dev for test dependencies
- Configure flat layout with module-root = ""
- Fix pre-existing test failures (updated error message, optional mock)
- Add uv.lock and dist/ to .gitignore
- uv run pytest (39 passed) and uv build both work
https://claude.ai/code/session_01DoiJf9Gbvbw2asN9yvP6dx
