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.ts

@@ -0,0 +1 @@
+export { useColorScheme } from 'react-native';

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';
+}

packages/voice-mobile/hooks/use-theme-color.ts

@@ -0,0 +1,21 @@
+/**
+ * Learn more about light and dark modes:
+ * https://docs.expo.dev/guides/color-schemes/
+ */
+
+import { Colors } from '@/constants/theme';
+import { useColorScheme } from '@/hooks/use-color-scheme';
+
+export function useThemeColor(
+  props: { light?: string; dark?: string },
+  colorName: keyof typeof Colors.light & keyof typeof Colors.dark
+) {
+  const theme = useColorScheme() ?? 'light';
+  const colorFromProps = props[theme];
+
+  if (colorFromProps) {
+    return colorFromProps;
+  } else {
+    return Colors[theme][colorName];
+  }
+}