feat: add github workflows

.github/workflows/phpstan.yml

@@ -0,0 +1,22 @@
+name: PHPStan
+
+on: [push, pull_request]
+
+jobs:
+  phpstan:
+    name: phpstan
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: '8.3'
+          coverage: none
+
+      - name: Install composer dependencies
+        uses: ramsey/composer-install@v2
+
+      - name: Run PHPStan
+        run: ./vendor/bin/phpstan --error-format=github

.github/workflows/phpunit.yml

@@ -0,0 +1,38 @@
+name: phpunit
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: true
+      matrix:
+        os: [ubuntu-latest]
+        php: [8.3]
+        dependency-version: [prefer-lowest, prefer-stable]
+
+    name: P${{ matrix.php }} - ${{ matrix.dependency-version }} - ${{ matrix.os }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Cache dependencies
+        uses: actions/cache@v3
+        with:
+          path: ~/.composer/cache/files
+          key: dependencies-php-${{ matrix.php }}-composer-${{ hashFiles('composer.json') }}
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: dom, curl, libxml, mbstring, zip, pcntl, pdo, sqlite, pdo_sqlite, bcmath, soap, intl, gd, exif, iconv, imagick
+          coverage: none
+
+      - name: Install dependencies
+        run: composer update --${{ matrix.dependency-version }} --prefer-dist --no-interaction
+
+      - name: Execute tests
+        run: vendor/bin/phpunit