feat: auto-generate manifest

src/app/opengraph-image.tsx

@@ -1,6 +1,6 @@
 import { ImageResponse } from "next/og";
 
-export const alt = "Farcaster Frames V2 Demo";
+export const alt = process.env.NEXT_PUBLIC_FRAME_NAME || "Frames V2 Demo";
 export const size = {
   width: 600,
   height: 400,
@@ -8,11 +8,13 @@ export const size = {
 
 export const contentType = "image/png";
 
+// dynamically generated OG image for frame preview
+// TODO: make this dynamic with user info (like robin's example)
 export default async function Image() {
   return new ImageResponse(
     (
       <div tw="h-full w-full flex flex-col justify-center items-center relative bg-white">
-        <h1 tw="text-6xl">Frames v2 Demo</h1>
+        <h1 tw="text-6xl">{alt}</h1>
       </div>
     ),
     {