site: drop PWA manifest from marketing site (SEO site, not an app)

Remove the web-app manifest link + manifest.ts route so bargevasat.ir no longer
triggers an "install/add to home screen" prompt. It's a plain marketing/SEO
site now. Only the game app (app.bargevasat.ir) remains a PWA.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

site/app/layout.tsx

@@ -41,7 +41,8 @@ export const metadata: Metadata = {
     images: ["/og.png"],
   },
   icons: { icon: "/icon.svg", apple: "/icon.svg" },
-  manifest: "/manifest.webmanifest",
+  // No web-app manifest on the marketing site — it's a plain SEO site, not an
+  // installable PWA. Only the game app (app.bargevasat.ir) is a PWA.
 };
 
 export const viewport: Viewport = {

site/app/manifest.ts

@@ -1,20 +0,0 @@
-import type { MetadataRoute } from "next";
-
-export const dynamic = "force-static";
-
-export default function manifest(): MetadataRoute.Manifest {
-  return {
-    name: "برگ وسط — بازی حکم آنلاین",
-    short_name: "برگ وسط",
-    description: "بازی حکم ایرانی آنلاین با دوستان و هوش مصنوعی.",
-    start_url: "/",
-    display: "standalone",
-    background_color: "#070b18",
-    theme_color: "#070b18",
-    dir: "rtl",
-    lang: "fa",
-    icons: [
-      { src: "/icon.svg", sizes: "any", type: "image/svg+xml", purpose: "any" },
-    ],
-  };
-}