Site reorg: Remove site/ subpath (#306)

Unfortunately, for proper package pathing, need to remove the `site/`
subpath. This includes:
- Moving everything back into root
- Adding a `copy-site.sh` script to copy resources into `mkdocs/site/`
before building the site with mkdocs.
- Also update examples to ensure all are loading the local sw.js / ui.js
- Consolidate examples in `docs/examples`
- Consolidate assets under src/assets/
- Move `favicons` to root
- Reformat and relint
- Tests: update playwright tests to use mkdocs output, add test for
embed in docs
- bump to 2.0.0-beta.2

.github/workflows/integration.yaml

@@ -29,5 +29,10 @@ jobs:
       - name: Playwright Install Browsers
         run: yarn playwright install
 
+      - uses: actions/setup-python@v4
+        with:
+          python-version: 3.x
+      - run: pip install -r mkdocs/requirements.txt
+
       - name: Playwright Run Tests
         run: yarn run playwright test