It is possible for prevtx to be larger than max packet size, so for shared outputs (currently only the funding tx) we add support for sending the `txid` only across the wire and filling in the prevtx locally.
Changelog-None
New daemon process means we don’t have to deal with gossip, so that gets removed along with error cleanup and a refactoring of how we calculating PDBT diffs.
Takes the dualopen collaborative transaction building and makes it available for other daemons to use
Changelog-Added: Added interactive transaction building routine
