chore: show theme selector in demo website only

src/components/dashboard/dashboard-header.tsx

@@ -29,6 +29,9 @@ export function DashboardHeader({
   breadcrumbs,
   actions,
 }: DashboardHeaderProps) {
+  // if is demo website, allow user to access admin and user pages, but data is fake
+  const isDemo = process.env.NEXT_PUBLIC_DEMO_WEBSITE === 'true';
+
   return (
     <header className="flex h-(--header-height) shrink-0 items-center gap-2 border-b transition-[width,height] ease-linear group-has-data-[collapsible=icon]/sidebar-wrapper:h-(--header-height)">
       <div className="flex w-full items-center gap-1 px-4 lg:gap-2 lg:px-6">
@@ -69,7 +72,7 @@ export function DashboardHeader({
         <div className="ml-auto flex items-center gap-3 px-4">
           {actions}
 
-          <ThemeSelector />
+          {isDemo && <ThemeSelector />}
           <ModeSwitcher />
           <LocaleSwitcher />
         </div>