fix scope in new test and workflow for appharness

.github/workflows/integration_app_harness.yml

@@ -51,6 +51,7 @@ jobs:
           SCREENSHOT_DIR: /tmp/screenshots
           REDIS_URL: ${{ matrix.state_manager == 'redis' && 'redis://localhost:6379' || '' }}
         run: |
+          poetry run playwright install --with-deps
           poetry run pytest tests/integration
       - uses: actions/upload-artifact@v4
         name: Upload failed test screenshots

tests/integration/test_stateless_app.py

@@ -21,7 +21,7 @@ def StatelessApp():
     app.add_page(index)
 
 
-@pytest.fixture(scope="module")
+@pytest.fixture(scope="session")
 def stateless_app(tmp_path_factory) -> Generator[AppHarness, None, None]:
     """Create a stateless app AppHarness.