fix(ci): use GITHUB_WORKSPACE instead of pwd for composer docker run volume

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitea/workflows/deploy.yaml

@@ -19,7 +19,7 @@ jobs:
       - name: Install Composer dependencies
         run: |
           docker run --rm \
-            -v "$(pwd):/app" \
+            -v "$GITHUB_WORKSPACE:/app" \
             -w /app \
             composer:2 install --no-dev --no-interaction --prefer-dist --optimize-autoloader