Migrate lint/format tooling to Ruff, update CI matrix, and stabilize cross-platform/firefox tests #1

	name: Lint and Format Check

	on: [push, pull_request]

	jobs:
	ruff:
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v4

	- name: Set up Python
	uses: actions/setup-python@v5
	with:
	python-version: "3.13"

	- name: Install dev dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements-dev.txt

	- name: Ruff format check
	run: \|
	python -m ruff format --check src/ utest/

	- name: Ruff lint
	run: \|
	python -m invoke lint

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