feat(behaviours): add BehavioursLoader to main barrel export

- Export BehavioursLoader from root package for convenience
- Users can now import from either:
  - @fergusbisset/nhs-fdp-design-system (main barrel)
  - @fergusbisset/nhs-fdp-design-system/behaviours/react (specific)
- Provides flexibility in import patterns

Author: Fergus Bisset

src/index.ts

@@ -26,5 +26,9 @@ export { BrandThemeProvider, useBrand } from './themes/BrandThemeProvider';
 // Font loading utilities
 export * from './styles/font-config';
 
+// Behaviours - React component for SSR-safe behaviour initialization
+export { BehavioursLoader } from './behaviours/react.js';
+export type { BehavioursLoaderProps } from './behaviours/react.js';
+
 // Brand assets and helpers (logos, enums, and utilities)
 export { BrandKey, LogoVariant, getBrandLogo, brandLogos } from './assets/brand';