feat(🧪): add WebGPU CTS integration for React Native

Add support for running the WebGPU Conformance Test Suite in React Native:

- Add sync-cts.sh script to copy and adapt CTS files for Metro bundler
- Add CTSScreen component with UI for running tests
- Add React Native runtime (loader.ts, runtime.ts) for CTS execution
- Add polyfills for Event, EventTarget, MessageEvent
- Stub Node.js-specific code (fs, perf_hooks)
- Generate static imports for all spec files (Metro doesn't support dynamic imports)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: wcandillon

apps/example/metro.config.js

@@ -12,6 +12,7 @@ const customConfig = {
   watchFolders: [root],
   resolver: {
     ...defaultConfig.resolver,
+    sourceExts: [...defaultConfig.resolver.sourceExts, 'cjs'],
     extraNodeModules: {
       'three': threePackagePath,
     },