Minor Changes

• ba99bda: Add the Bloom theme variant and a theme config key.

  NativeUIProvider now accepts theme: 'default' | 'bloom' | ThemeVariant. A theme variant bundles a complete visual identity (colour palette, corner radii, elevation, type density, and default fonts) behind one name and restyles every component. The new Bloom variant is a soft, rounded look: violet/pink accents, rounded corners, purple-tinted neutrals, and Outfit + Plus Jakarta Sans typography. The original look ships unchanged as the Aurora ('default') variant, so existing apps are unaffected.

  FontFamilies gains an optional display group so a variant can pair a heading family with a separate body family. New exports: THEME_VARIANTS, defaultThemeVariant, bloomThemeVariant, resolveThemeVariant, defaultColorPalette, bloomColorPalette, BLOOM_PRESETS, bloomFontFamilies, and the types ThemeVariant, ThemeVariantName, ColorPalette, TextRamp, SemanticRamp, NeutralRamp, BloomPreset, BorderRadiusScale.