Fix Paystack Wallet Sync

I already connected Paystack to my site, yet every time I complete a payment the money settles in Paystack but my on-site wallet stays empty. The job is to trace and correct whatever is blocking the webhook/transaction callback so that, for each one-time payment, the wallet is credited instantly with the full payment details (amount, reference, status, date).

Current status
• Paystack keys are saved and the checkout page processes cards successfully.
• The wallet logic exists but is not being triggered after payment.

What I need from you
1. Review the existing integration, including callback URL, event listener, and signature validation.
2. Update or rewrite the handler so it records every successful charge and pushes the transaction ID, amount, and any other data exposed by the Paystack API into the wallet table.
3. Test end-to-end with at least one live ₦100 transaction to prove the wallet balance updates correctly.
4. Hand over the final, commented code plus a short note on how to add additional fields in the future.

No design work is required—just the functional link between Paystack and the wallet. I’ll provide server access, Paystack keys, and test credentials as soon as we start.