theme.ts owns the ThemePreference (light, dark, system) and ResolvedTheme (light, dark) types, and the option list (value, icon, common label key) that every theme control renders in the same order.
provider.tsx owns the provider configuration: the data-theme attribute, system as the default preference, and the CSP nonce.
hooks.ts separates the two questions a component can ask. useThemePreference returns what the user chose and is for theme controls. useResolvedTheme returns the light or dark value in effect and is for icons, editors, charts, and Marketplace links. A Marketplace link never receives system.
theme-selector.tsx is the standalone icon menu for pages without the account menu.

Theme copy lives in the common namespace (theme.label, theme.light, theme.dark, theme.system) because console, share, auth, and Goto Anything surfaces all load it. Surface-specific descriptions stay with their surface.