fix: improve mobile workbench controls

app/layout.tsx

@@ -1,4 +1,4 @@
-import type { Metadata } from "next";
+import type { Metadata, Viewport } from "next";
 import { MapToaster } from "@/features/map/core/components/notice";
 import "katex/dist/katex.min.css";
 import "streamdown/styles.css";
@@ -9,6 +9,11 @@ export const metadata: Metadata = {
   description: "Agent 编排型沉浸式排水管网业务工作台"
 };
 
+export const viewport: Viewport = {
+  width: "device-width",
+  initialScale: 1
+};
+
 export default function RootLayout({
   children
 }: Readonly<{