feat: initialize root layout with Geist font, metadata, and theme provider

app/layout.tsx

@@ -1,4 +1,4 @@
-import type { Metadata } from "next";
+import type { Metadata, Viewport } from "next";
 import { Geist } from "next/font/google";
 import { ThemeProvider } from "next-themes";
 import "./globals.css";
@@ -7,6 +7,11 @@ const defaultUrl = process.env.VERCEL_URL
   ? `https://${process.env.VERCEL_URL}`
   : "http://localhost:3000";
 
+export const viewport: Viewport = {
+  width: "device-width",
+  initialScale: 1,
+};
+
 export const metadata: Metadata = {
   metadataBase: new URL(defaultUrl),
   title: "Next.js and Supabase Starter Kit",