feat: add verified desktop ChatGPT subscription connection

proxy.ts

@@ -0,0 +1,17 @@
+import { NextResponse, type NextRequest } from "next/server";
+import { desktopAPIAuthorized } from "./src/server/desktop-access.ts";
+
+/** Applies to every API method, including SSE and spending/settings routes.
+ * No public callback or worker bypass: internal jobs call server functions,
+ * and any legitimate self-HTTP request must carry the private capability. */
+export function proxy(request: NextRequest) {
+	if (!desktopAPIAuthorized(request.headers)) {
+		return NextResponse.json(
+			{ error: "Desktop API access requires the trusted LearnHarness window." },
+			{ status: 403, headers: { "Cache-Control": "no-store" } },
+		);
+	}
+	return NextResponse.next();
+}
+
+export const config = { matcher: "/api/:path*" };