Support async payments in BOLT 12 (Blinded Paths, Async Payments, Bolt12, Offer)

https://github.com/lightningdevkit/rust-lightning/pull/3207

Host: vincenzopalazzo  -  PR author: valentinewallace

Notes

Question

  1. Did you review ldk/3207? Is it a Concept ACK, approach ACK, tested ACK, or NACK?
  2. Did you review the blot/1149?
  3. Is blots/1149 possible to implement on the current spec? If not what is the feature that we need?
  4. What type of feature bit does blots#1149 introduce?
  5. Why does commit https://github.com/lightningdevkit/rust-lightning/pull/3207/commits/8946dc97bd8ce9165392d5e270a134d74afc4f82 need to store the invoice_request? Where is it used after being stored?