Add CI workflow with badge and tooling #3

	name: CI

	on:
	pull_request:
	branches: [master]
	push:
	branches: [master]
	workflow_dispatch:

	permissions:
	contents: read

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	build:
	name: build
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v5
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: "3.3"
	bundler-cache: true
	- name: Build gem
	run: bundle exec rake build

	test:
	name: test (${{ matrix.ruby-version }})
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	ruby-version: ["2.7", "3.1", "3.2", "3.3"]
	steps:
	- uses: actions/checkout@v5
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: ${{ matrix.ruby-version }}
	bundler-cache: true
	- name: Run tests
	run: bundle exec rspec

	lint:
	name: lint
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v5
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: "3.3"
	bundler-cache: true
	- name: Run RuboCop
	run: bundle exec rubocop

	audit:
	name: audit
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v5
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: "3.3"
	bundler-cache: true
	- name: Run bundler-audit
	run: bundle exec bundler-audit check --update

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