[FEAT]: Add messages when handling the purchase process with toast notification

[fathima200]

📝 Pull Request Title: [FEAT]: Add messages when handling the purchase process with toast notification

🛠️ Issue

• Closes [FEAT]: Add messages when handling the purchase process #198

📖 Description

Added dialog messages (toasts) to the purchase process on the shopping/[id] page as requested. The Trustless Work API was already implemented, and this change introduces success or error notifications after payment attempts, improving user feedback.

✅ Changes made

• I added Shadcn toast notifications in shopping/[id]/page.tsx to display success or error messages during the payment process.
• Wrapped the onPay function in a try/catch block to handle payment outcomes and trigger appropriate toasts.
• Updated locales/en.ts and locales/es.ts with translations for success ("Payment Successful"/"Pago Exitoso") and error ("Payment Failed"/"Error en el Pago") messages.

🖼️ Media (screenshots/videos)

• Error toast displayed on payment attempt (due to API 401):
  

📜 Additional Notes

• Currently, the payment process fails with a 401 Unauthorized error (likely wallet auth or backend setup), triggering the error toast. The success toast is implemented and will display once the API succeeds.