add discord link back

web/app/header.tsx

@@ -1,6 +1,7 @@
 import Link from "next/link"
 
 const navigation = [
+  { name: 'Discord', href: 'https://discord.gg/MrfB5FbNWN' },
   { name: 'Github', href: 'https://github.com/jmorganca/ollama' },
   { name: 'Download', href: '/download' },
 ]