feat: restrict database management page to admin users only

apps/Frontend/src/App.tsx

@@ -52,6 +52,7 @@ function Router() {
       <ProtectedRoute
         path="/database-management"
         component={() => <DatabaseManagementPage />}
+        adminOnly
       />
       <ProtectedRoute path="/reports" component={() => <ReportsPage />} />
       <ProtectedRoute path="/cloud-storage" component={() => <CloudStoragePage />} />

apps/Frontend/src/components/layout/sidebar.tsx

@@ -80,6 +80,7 @@ export function Sidebar() {
         name: "Database Management",
         path: "/database-management",
         icon: <Database className="h-5 w-5" />,
+        adminOnly: true,
       },
       {
         name: "Settings",