feat: migrate examples from prototype and add CSS modules support

- Migrate HTML and React demo applications from prototype to examples/ directory
- Add examples to workspace configuration with selective build support
- Update workspace scripts for library-only builds (build:libs) and example dev servers
- Fix React MediaProvider context conflicts by consolidating exports
- Add esbuild-css-modules-plugin for CSS modules support in React package
- Configure tsup for flattened output structure with CSS processing
- Update package exports and imports for new @vjs-10/* scoped packages

🤖 Generated with [Claude Code](https://claude.ai/code)

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

examples/react-demo/src/main.tsx

@@ -0,0 +1,19 @@
+import React from 'react';
+import ReactDOM from 'react-dom/client';
+import { MediaProvider, Video, MediaSkinDefault } from '@vjs-10/react';
+
+const DemoPlayer = () => {
+  return (
+    <MediaProvider>
+      <MediaSkinDefault>
+        {/* @ts-ignore */}
+        {/* <Video muted src="https://www.w3schools.com/html/mov_bbb.mp4" /> */}
+        <Video muted src="https://stream.mux.com/a4nOgmxGWg6gULfcBbAa00gXyfcwPnAFldF8RdsNyk8M.m3u8" />
+      </MediaSkinDefault>
+    </MediaProvider>
+  );
+};
+
+ReactDOM.createRoot(document.getElementById('root')!).render(
+  <DemoPlayer />
+);