Refactor registration and dashboard features to support invite codes and Bunny uploads

- Moved registration logic to a new client component for better separation of concerns.
- Integrated invite code requirement based on feature flags in the registration process.
- Enhanced dashboard functionality to conditionally enable Bunny uploads based on feature flags.
- Updated various components and API routes to check for Bunny uploads and Stripe billing feature flags.
- Added new feature flag utilities for managing feature toggles in the application.

app/(dashboard)/settings/settings-page-client.tsx

@@ -33,7 +33,9 @@ interface NotificationSettings {
 }
 
 interface BillingOverview {
+  isEnabled: boolean;
   isConfigured: boolean;
+  status: 'disabled' | 'ready' | 'misconfigured';
   checkoutAvailable: boolean;
   portalAvailable: boolean;
   subscription: {
@@ -320,6 +322,10 @@ export default function SettingsPage({ billingOnly = false }: { billingOnly?: bo
               <Skeleton className="h-4 w-full" />
               <Skeleton className="h-10 w-44 rounded-md" />
             </div>
+          ) : !billing.isEnabled ? (
+            <div className="rounded-md border border-muted bg-muted/40 p-4 text-sm text-muted-foreground">
+              Stripe billing is disabled by this host. Workspace creation is unrestricted in this environment.
+            </div>
           ) : !billing.isConfigured ? (
             <div className="rounded-md border border-amber-500/30 bg-amber-500/10 p-4 text-sm text-amber-700 dark:text-amber-400">
               Stripe is not configured yet. Add your Stripe environment variables before using billing.