feat: initialize voice-mobile React Native app with NativeWind v5

- Created new Expo app with SDK 54+ and Expo Router
- Installed and configured NativeWind v5 for Tailwind styling
- Upgraded voice-assistant to React 19 for consistency
- Kept voice-mobile outside workspace to avoid Metro bundler conflicts
- Disabled React Compiler experimental feature for stability

Setup includes:
- postcss.config.mjs with Tailwind PostCSS plugin
- global.css with Tailwind and NativeWind imports
- metro.config.js with NativeWind wrapper
- lightningcss pinned to 1.30.1 for stability

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

packages/voice-mobile/hooks/use-color-scheme.web.ts

@@ -0,0 +1,21 @@
+import { useEffect, useState } from 'react';
+import { useColorScheme as useRNColorScheme } from 'react-native';
+
+/**
+ * To support static rendering, this value needs to be re-calculated on the client side for web
+ */
+export function useColorScheme() {
+  const [hasHydrated, setHasHydrated] = useState(false);
+
+  useEffect(() => {
+    setHasHydrated(true);
+  }, []);
+
+  const colorScheme = useRNColorScheme();
+
+  if (hasHydrated) {
+    return colorScheme;
+  }
+
+  return 'light';
+}