Add GitHub Actions CI workflow for PHP checks

- Introduced `.github/workflows/php.yml` for continuous integration.
- Configured tasks for code validation, style checks, static analysis, testing, and coverage reporting.
- Ensured compatibility with PHP 8.2.16 and required extensions.

Author: georgedeploy

.github/workflows/php.yml

@@ -0,0 +1,54 @@
+name: checks
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: '8.2.16'
+        extensions: mbstring, intl
+
+    - name: Validate composer.json and composer.lock
+      run: composer validate --strict
+
+    - name: Cache Composer packages
+      id: composer-cache
+      uses: actions/cache@v3
+      with:
+        path: vendor
+        key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-php-
+
+    - name: Install dependencies
+      run: composer install --prefer-dist --no-progress --ignore-platform-reqs
+
+    - name: Run style fixer
+      run: composer run-script cs
+
+    - name: Run psalm
+      run: composer run-script sca
+
+    - name: Run tests
+      run: composer run-script test
+
+    - name: Run type coverage
+      run: composer run-script type
+
+    - name: Run test coverage
+      run: composer run-script coverage