Reactivate Checkstyle #2815

	name: CodeQuality
	on:
	workflow_dispatch:
	merge_group:
	pull_request:
	push:
	branches:
	- main
	- 'KeY-*'

	jobs:
	checkerFramework:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Set up JDK 21
	uses: actions/setup-java@v4
	with:
	java-version: 21
	distribution: 'corretto'
	cache: 'gradle'
	- name: Setup Gradle
	uses: gradle/actions/setup-gradle@v4
	- name: Build with Gradle
	run: ./gradlew -DENABLE_NULLNESS=true compileTest

	formatting:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-java@v4
	with:
	distribution: 'corretto'
	java-version: '21'
	cache: 'gradle'
	- name: Build with Gradle
	run: ./gradlew --parallel --continue spotlessCheck

	checkstyle_changed_files:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	ref: ${{ github.event.pull_request.head.sha }}
	- run: "git diff --name-only origin/main"
	- uses: actions/setup-java@v4
	with:
	distribution: 'corretto'
	java-version: '21'
	cache: 'gradle'
	- name: Build with Gradle
	run: ./gradlew --parallel --continue checkstyleMainChanged
	- run: "cat build/reports/checkstyle/main_diff.html >> $GITHUB_STEP_SUMMARY"
	- name: Archive code coverage results
	uses: actions/upload-artifact@v4
	with:
	name: checkstyle-report
	path: build/reports/checkstyle/main_diff.html
	- uses: github/codeql-action/upload-sarif@v3
	if: success() \|\| failure()
	with:
	sarif_file: build/reports/checkstyle/main_diff.sarif.json

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