Enhance root layout and admin interface for better usability

- Updated the root layout to include a mobile menu toggle, improving navigation on smaller screens.
- Refactored navigation links and language/theme selection for better organization and accessibility.
- Added overflow handling for admin navigation and tables to ensure proper display on smaller screens.
- Improved translations for menu toggle accessibility in both Russian and English.

frontend/src/routes/admin/users.tsx

@@ -49,6 +49,7 @@ function AdminUsersPage() {
 
       {data && (
         <>
+          <div className="overflow-x-auto">
           <table className="w-full text-left text-sm">
             <thead>
               <tr className="border-b border-border text-muted-foreground">
@@ -81,6 +82,7 @@ function AdminUsersPage() {
               ))}
             </tbody>
           </table>
+          </div>
 
           {data.items.length === 0 && <p className="text-sm text-muted-foreground">{t('admin.users.empty')}</p>}