Move sign out command before account deletion and modify private path prefixes

The sign out command is moved ahead of the account deletion service to ensure users are logged out before their account gets deleted. The "/join" prefix is removed from the list of private path prefixes. Additionally, a global loader component is added to the join loading page.

apps/web/app/join/loading.tsx

@@ -0,0 +1,3 @@
+import { GlobalLoader } from '@kit/ui/global-loader';
+
+export default GlobalLoader;