author: akumaigorodski
disposable field
This document defines a disposable field that may be returned by SERVICE along with a payment request in the second LNURL-pay callback.
WALLET to decide whether the initial LNURL link will be stored locally for later reuse or erased. If disposable is null, it should be interpreted as true, so if SERVICE intends its LNURL links to be stored it must return disposable: false.