chore: bump version to 3.1.1 in package.json; refactor mobile navigation components and improve layout structure (#472)

- Updated version to 3.1.1 in package.json.
- Refactored mobile navigation components to enhance structure and usability.
- Adjusted layout components to improve responsiveness and visual consistency.
- Introduced shared mobile navigation components for better code reuse.

apps/web/app/[locale]/home/(user)/billing/_lib/server/user-billing.service.ts

@@ -109,7 +109,7 @@ class UserBillingService {
           planId,
           customerId,
           accountId,
-          error: message
+          error: message,
         },
         `Checkout session not created due to an error`,
       );