ci: add mutation testing workflow with Infection #1

	name: Mutation Testing

	on:
	push:
	branches:
	- main
	pull_request:

	permissions:
	contents: read

	jobs:
	mutation-testing:
	name: Mutation Testing
	runs-on: ubuntu-24.04

	steps:
	- name: Checkout code
	uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6

	- name: Setup PHP
	uses: shivammathur/setup-php@44454db4f0199b8b9685a5d763dc37cbf79108e1 # v2
	with:
	php-version: '8.2'
	extensions: json
	coverage: xdebug
	tools: composer:v2

	- name: Get composer cache directory
	id: composer-cache
	run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT

	- name: Cache dependencies
	uses: actions/cache@9255dc7a253b0ccc959486e2bca901246202afeb # v5
	with:
	path: ${{ steps.composer-cache.outputs.dir }}
	key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
	restore-keys: ${{ runner.os }}-composer-

	- name: Install dependencies
	run: composer update -n --prefer-dist

	- name: Run mutation testing
	run: vendor/bin/infection --threads=max --min-msi=87 --min-covered-msi=87

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