Migrate layout

app/src/components/layout/Header.tsx

@@ -0,0 +1,22 @@
+import React from 'react';
+import { Group, Text } from '@mantine/core';
+import UserMenu from '../navigation/UserMenu';
+import WorkspaceSwitcher from '../navigation/WorkspaceSwitcher';
+import WorkspaceSettings from '../settings/workspace/WorkspaceSettings';
+
+const Header: React.FC = () => {
+  return (
+    <Group justify="space-between" h={60} px="md">
+      <Text fw={700} size="lg">
+        Lemma
+      </Text>
+      <Group>
+        <WorkspaceSwitcher />
+        <UserMenu />
+      </Group>
+      <WorkspaceSettings />
+    </Group>
+  );
+};
+
+export default Header;