Renamed topbar to header

ui/src/app/layout.tsx

@@ -1,6 +1,6 @@
 import React from 'react';
 import RecoilRootWrapper from '@app/recoil-root-wrapper';
-import Topbar from '@/components/Topbar';
+import Header from '@/components/Header';
 import { Inter } from 'next/font/google';
 import { Box, MantineProvider } from '@mantine/core';
 import { ModalsProvider } from '@mantine/modals';
@@ -27,7 +27,7 @@ export default function RootLayout({ children }: { children: React.ReactNode })
           <MantineProvider>
             <Notifications />
             <ModalsProvider>
-              <Topbar />
+              <Header />
               <Box p='xl' pt='sm' className='h-full'>
                 {children}
               </Box>