Add Sites & Subnets management page

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 705f2157-ef97-4fbd-89e4-8c7f2ecaea90
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/7ed01c5f-a82d-405a-b728-b2e3d127c60c/ca28303a-582b-45b8-9072-25d4361e3211.jpg

client/src/layouts/dashboard-layout.tsx

@@ -30,6 +30,7 @@ import {
   ShieldAlert,
   Filter,
   ClipboardList,
+  Building2,
 } from "lucide-react";
 import { useMobile } from "@/hooks/use-mobile";
 import { useToast } from "@/hooks/use-toast";
@@ -56,6 +57,7 @@ const menuSections: MenuSection[] = [
       { title: "Organizational Units", path: "/organizational-units", icon: <FolderClosed className="h-4 w-4" /> },
       { title: "Computers", path: "/computers", icon: <Monitor className="h-4 w-4" /> },
       { title: "Domains", path: "/domains", icon: <Globe className="h-4 w-4" /> },
+      { title: "Sites & Subnets", path: "/sites", icon: <Building2 className="h-4 w-4" /> },
     ],
   },
   {