ExamplesThemeTheme — controlsCopy PageToggle and light/dark/system selector.Theme controls`ThemeProvider` syncs with `preferences` via `applyThemePreference` on change.ThemeCard surfaceMuted surfaceSecondary surfaceDataTable — URL syncPagination, search, and filters reflected in the query string.Uploader — basicSpreadsheet import dialog with template download, validation, and a mock upload handler.