Serverless Payjoin BIP draft has been submitted

A few questions to reach consensus on:

- WebTransport or Nostr or WebSockets or ?

- Is the IK cryptosystem ideal?

- Take this opportunity to ship long lived contacts?

- How should pubkeys be encoded?

If you think it's Nostr's time to shine or you want to see BIP 47 (or some alternate?) contact system baked in, now's the time to speak up so we have a unified front moving forward.