Description
Is your feature request related to a problem? Please describe.
For backwards compat reasons, we disabled the new v2 proof scheme for tap channels. We should enable them.
Describe the solution you'd like
This is related to #1573. In order to not break the existing channels, we need a mechanism to signal: a funding output that includes the new commitments, and also commitment/HTLC outputs that include the new commitments.
For the funding output, we can use a new channel type feature bit as mentioned in the channels. That covers a scenario where new channels will use proof v2 all throughout.
We can also cover new channels if we use something like the proposed feature bits in the channel_reest message to signal that we support this new feature. In that case, the very next commitment created would utilize the new v2 proofs. Care here should be taken to ensure that force clsoes and breaches work as normal.