Modernize packaging and CI with pyproject.toml and uv

[izkgao]

Closes #158.

Summary

Modernize packaging and CI around pyproject.toml and uv, move CI linting to ruff, and raise the minimum supported Python version to 3.10 while keeping the existing pip install . flow documented for users.

Changes

Packaging & dependencies

• Replace setup.py with a PEP 621 pyproject.toml
• Add uv.lock for reproducible dependency resolution
• Add .python-version and set the minimum supported Python version to 3.10
• Define dependency groups for lint, test, docs, and dev
• Move selenium into the optional browser extra

CI workflows

• Switch GitHub Actions jobs to astral-sh/setup-uv@v7 with locked environment syncs
• Update style check CI from flake8 to ruff check
• Update the unit test matrix to Python 3.10 through 3.14
• Build docs in CI with uv sync --group docs and sphinx-build
• Bump actions/checkout to v6

Docs & developer guidance

• Pin docs/requirements.txt via uv export for Read the Docs
• Add fail_on_warning: true and install the package itself in .readthedocs.yaml
• Update README.md to keep the existing pip/pytest workflow and add uv as an alternative contributor setup
• Update the quickstart docs to call out the Python 3.10+ requirement and the optional browser extra

Compatibility notes

• End-user installation remains pip install .
• Existing style helper scripts remain available for developers who already use them
• The main user-visible compatibility change in this PR is the minimum supported Python version becoming 3.10

How to test

uv sync
uv run pytest -v tests/
uv run ruff check
uv run sphinx-build -W -b html docs/source docs/build/html