Agent Skills: theming

Scaffold a unified, cross-platform color theme system into an Expo Router app. Sets up semantic system colors (resolved from native iOS labels and Android Material You dynamic colors), brand colors, automatic dark/light re-rendering, the React Navigation ThemeProvider, and a useColors() / useTheme() context hook. Use whenever a user wants to set up theming, dark mode, dynamic or Material You colors, a unified color system, or a useColors/useTheme hook in an Expo / React Native app, even if they do not name a specific approach.