- add pyproject.toml and uv.lock pinning teedoc 1.37.9 with the twelve
plugins listed in site_config.json, plus setuptools: babel's
babel.messages.frontend imports distutils, which is no longer part of
the standard library on Python 3.12+
- declare Python >= 3.10, the floor required by the pinned setuptools
- replace the pip preview steps in README.md and share_docs/zh/add_doc.md
with "uv sync && uv run teedoc serve"; the plugins now come from the
lockfile, so teedoc install is no longer needed
