Mastercard/crossborder-services-reference-app ? reverse-engineered prompt

Build me a simple Java reference app that shows how to connect to Mastercard Cross Border Services APIs and try the main flows end to end.

I want it to run from the IDE or with Maven, use Spring, and be easy to configure with a consumer key and a p12 signing file in the resources folder. Please include examples for requesting quotes, making a payment, checking a payment, and canceling a payment. It should also support the option to send and receive encrypted payloads if I turn that on, and have a plain JSON example too.

Make it feel like a hands on demo project, with test classes or sample methods I can run directly, and clear spots where I can edit the sample request values. If you need current API details, look up the latest Mastercard docs online first.