feat: add landing page copy and styles for English and Amharic versions

- Introduced `landing-copy.ts` containing text for the public landing page, supporting both English and Amharic languages.
- Added `landing.css` for styling the landing page, ensuring scoped styles to prevent conflicts with other app styles.
- Implemented smooth scrolling and animations for a better user experience.

apps/backoffice/src/main.tsx

@@ -39,7 +39,7 @@ window.__USER_MANAGEMENT_BRANDING__ = {
   organizationName: 'Ethiopian Maritime Authority',
   logoSrc: '/assets/emaLogo.jpg',
   logoAlt: 'EMA Logo',
-  homePath: '/',
+  homePath: '/dashboard',
   moduleBasePath: '/user-management',
   backToAppPath: '/dashboard',
   backToAppLabel: 'Back to dashboard',