Integrate Online Payment Feature DANA

I already have a running platform and now it’s time to let customers pay me directly on-site. My main goal is to add a full online-payment system—everything from the checkout UI to secure backend processing and callback handling.

Here’s what I need from you:
• Select and connect a reliable gateway (Midtrans, Xendit, PayPal, Stripe, or another you recommend) using their latest REST or JavaScript SDK.
• Build the front-end payment form, tokenisation flow, and clear error/success states that match the look of my current app.
• Implement the server-side endpoints to create charges, verify signatures, store basic transaction data, and send webhooks. My stack is flexible, so let me know whether you prefer Node.js, PHP, Python, or another language.
• Make sure everything is PCI-compliant, HTTPS-ready, and passes sandbox and live testing.
• Provide concise hand-off notes—environment variables, keys to swap, and a simple rollback plan.

Final acceptance: I can run one test card, see the transaction in the dashboard, receive the webhook, and the order status updates automatically on my side.