Remove the per-project files so we don't have to keep them in sync. GitHub's UI links to everything except the contributing guide, so add a section about that to the readme.
* update pre-commit hooks * add devcontainer * show url in publish environment * update actions versions * separate typing job * use dependabot grouped updates ignore upload/download-artifact until slsa updates * use sphinx.ext.extlinks instead of sphinx-issues * update editorconfig * update gitignore * update .readthedocs.yaml * license is txt, readme is md * use pyproject.toml and flit_core instead of setuptools add typed classifier add pyright config simplify urls * tox builds docs in place * add tox env to update all dev dependencies * update issue and pr templates * simplify matrix
