H0llyW00dzZ/pakasir-go-sdk — reverse-engineered prompt

Build me an unofficial Go library for integrating Pakasir payments into a Go app. I want a clean SDK that lets a developer create a payment transaction, cancel one, check transaction details, simulate a sandbox payment, parse incoming webhook notifications, and build a redirect payment URL without manually writing HTTP calls.

Please include support for QRIS, virtual account methods, PayPal, and typed transaction statuses like pending, completed, expired, and cancelled. It should be easy to set up with a project slug and API key, allow custom timeout, base URL, language, retry settings, and custom HTTP client. Errors should be friendly and available in English and Indonesian, but still easy to check in code.

Add QR code generation for QRIS payment strings so the app can return, save, or display a PNG. Include examples, tests, and simple generated gRPC services for transaction and payment simulation if that fits the current Go tooling. Look up current Pakasir API docs online if you need to.