Add auth and theme switcher

src/app/page.tsx

@@ -1,7 +1,14 @@
+import { Button } from "@/components/ui/button";
+
 export default function HomePage() {
   return (
     <div>
       ADMIN HOME
+      <div>
+        <Button className="bg-primary text-primary-foreground">
+          Themed Button
+        </Button>
+      </div>
     </div>
   );
 }