perf(map): reuse resources across routes

Preserve standard network layers between map pages while disposing route-owned overlays and controls to prevent memory growth.

src/app/(main)/(map)/layout.tsx

@@ -0,0 +1,9 @@
+"use client";
+
+import type { ReactNode } from "react";
+
+import MapComponent from "@components/olmap/core/MapComponent";
+
+export default function MapLayout({ children }: { children: ReactNode }) {
+  return <MapComponent>{children}</MapComponent>;
+}