fix: move viewport metadata to separate export

- Remove viewport from metadata export in layout.tsx
- Add separate viewport export following Next.js 14+ conventions
- Fixes unsupported metadata viewport warning

Author: michelroegl-brunner

src/app/layout.tsx

@@ -1,21 +1,26 @@
 import "~/styles/globals.css";
 
-import { type Metadata } from "next";
+import { type Metadata, type Viewport } from "next";
 import { Geist } from "next/font/google";
 
 import { TRPCReactProvider } from "~/trpc/react";
 
 export const metadata: Metadata = {
   title: "PVE Scripts local",
   description: "Manage and execute Proxmox helper scripts locally with live output streaming",
-  viewport: "width=device-width, initial-scale=1, maximum-scale=1",
   icons: [
     { rel: "icon", url: "/favicon.png", type: "image/png" },
     { rel: "icon", url: "/favicon.ico", sizes: "any" },
     { rel: "apple-touch-icon", url: "/favicon.png" },
   ],
 };
 
+export const viewport: Viewport = {
+  width: "device-width",
+  initialScale: 1,
+  maximumScale: 1,
+};
+
 const geist = Geist({
   subsets: ["latin"],
   variable: "--font-jetbrains-mono",