Rethink Multi-RFQ flows with Portfolio Pilot

[levmi]

When we move forward with the Portfolio Pilot on the edge node/RFQ side, we will need to update the Multi-Peer RFQ flows to properly handle multiple quotes. Multiple quotes would be possible in a variety of cases, but specifically, it would be quite relevant when there are certain buckets based on amounts and a payment send uses those quotes to fulfill the payment.

[GeorgeTsagk]

I'd change the issue name to
"Rethink multi-RFQ flows with portfolio pilot"

And a mental note for when we pick this up:

We'll have to outsource the "RFQ selection" to the portfolio pilot, instead of acquiring N-quotes with max amount.

Something to also check

• AuxTrafficShaper bandwidth should clamp available amount to the remaining RFQ amount. This way, if a "long living" RFQ is 90% depleted LND will only see the 10% of the remaining bandwidth, which is what we'll want.