ci: add Forgejo Actions workflow for PHP tests

The .github/workflows/ci.yml has a visibility guard that evaluates
to false on Forgejo, causing all jobs to fail in 1 second.

Co-Authored-By: Charon <charon@lethean.io>

.forgejo/workflows/ci.yml

@@ -0,0 +1,38 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: true
+      matrix:
+        php: [8.3, 8.4]
+
+    name: PHP ${{ matrix.php }}
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup PHP
+        uses: https://github.com/shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: dom, curl, libxml, mbstring, zip, pcntl, pdo, sqlite, pdo_sqlite
+          coverage: pcov
+
+      - name: Install dependencies
+        run: composer install --prefer-dist --no-interaction --no-progress
+
+      - name: Run Pint
+        run: vendor/bin/pint --test
+
+      - name: Run tests
+        run: vendor/bin/pest --ci --coverage