Refactor project structure and update assets

- Added new directories for Llms and Security components under src.
- Moved existing files into their respective directories for better organization.
- Updated file paths in imports to reflect the new structure.
- Replaced favicon.svg with a new version and updated its import path in index.html.
- Created a new LogoIcon component for the favicon with customizable colors.
- Added main and submenu link data files for navigation.
- Removed unused favicon.svg from public directory.
- Updated theme colors for a refreshed UI look.

frontend/src/assets/icons/index.ts

@@ -15,4 +15,4 @@ export { default as IconCheck } from './outlined/check.svg?react';
 
 // FILLED
 export { default as IconHomeFilled } from './filled/home.svg?react';
-export { default as IconUserFilled } from './filled/user.svg?react';
+export { default as IconUserFilled } from './filled/user.svg?react';