LNv2 LNURL #285
Description
Currently in Ecash App, LNURL is only supported using LNv1. This works, but the main downside is that federations need to be "whitelisted" in order to be used, which is just a burden on the recurringd operator.
We should implement LNURL for LNv2, which fixes this issue. We need to figure out how to do this in a backwards compatible way, and fall back to LNv1 when LNv2 is not available.