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

webmanifest.json

@@ -0,0 +1,16 @@
+{
+  "name": "ReplayWeb.page",
+  "short_name": "ReplayWeb.page",
+  "description": "A tool to explore and replay interactive archived web pages directly in the browser",
+  "icons": [
+    {
+      "src": "/favicons/icon-192.png",
+      "type": "image/png",
+      "sizes": "192x192"
+    },
+    { "src": "/favicons/icon-512.png", "type": "image/png", "sizes": "512x512" }
+  ],
+  "start_url": "/",
+  "display": "standalone",
+  "theme_color": "#ffffff"
+}