feat(pwa): install the chat as a standalone app

The chat page now exports Metadata that points at /chat.webmanifest and
declares appleWebApp for Safari's Add to Home Screen path (which
ignores manifest scope rules).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/app/dashboard/chat/page.tsx

@@ -1,10 +1,31 @@
 import { notFound } from "next/navigation";
+import type { Metadata } from "next";
 import { chatEnabled, getProvider } from "@/lib/chat";
 import { Topbar } from "@/components/layout/sidebar";
 import { ChatView } from "./chat-view";
 
 export const dynamic = "force-dynamic";
 
+/**
+ * A manifest distinct from the dashboard's, so the chat installs as its
+ * own app. The dashboard manifest is generated by next-pwa from
+ * next.config.js; this one is a static file in public/ and does not
+ * interfere with it.
+ *
+ * appleWebApp covers Safari's "Add to Home Screen", which ignores
+ * manifest scope rules — Apple treats the open page as a standalone
+ * bookmark, so the meta tags are what drive that path.
+ */
+export const metadata: Metadata = {
+  title: "Ask · MEGA INFRASTRUCTURE",
+  manifest: "/chat.webmanifest",
+  appleWebApp: {
+    capable: true,
+    title: "Ask",
+    statusBarStyle: "default",
+  },
+};
+
 export default function ChatPage() {
   // Same gate as the API route — the page must not exist when disabled.
   if (!chatEnabled()) notFound();