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/app/modal.tsx

@@ -0,0 +1,29 @@
+import { Link } from 'expo-router';
+import { StyleSheet } from 'react-native';
+
+import { ThemedText } from '@/components/themed-text';
+import { ThemedView } from '@/components/themed-view';
+
+export default function ModalScreen() {
+  return (
+    <ThemedView style={styles.container}>
+      <ThemedText type="title">This is a modal</ThemedText>
+      <Link href="/" dismissTo style={styles.link}>
+        <ThemedText type="link">Go to home screen</ThemedText>
+      </Link>
+    </ThemedView>
+  );
+}
+
+const styles = StyleSheet.create({
+  container: {
+    flex: 1,
+    alignItems: 'center',
+    justifyContent: 'center',
+    padding: 20,
+  },
+  link: {
+    marginTop: 15,
+    paddingVertical: 15,
+  },
+});