chore: implement unit tests

.github/workflows/unit-tests.yml

@@ -0,0 +1,33 @@
+name: Unit Tests
+
+on:
+  pull_request:
+    branches: ["main"]
+
+jobs:
+  unit:
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        php-version: ["8.2", "8.5"]
+
+    name: PHP ${{ matrix.php-version }}
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php-version }}
+          extensions: json, curl
+          coverage: none
+
+      - name: Install Composer dependencies
+        run: composer install --prefer-dist --no-progress --no-interaction
+
+      - name: Run unit tests
+        run: composer test:unit