The auctioneer will now provide a height hint along with every proposed
batch it sends to traders. This height hint is then used by each trader
to base off their absolute lease expiration height, such that they can
agree on the same value and avoid any divergences due to block
propagation discrepancies between them.
Because the batch Versions are in the order package, the use of
order.DefaultVersion is confusing and not clear to be related to the
version of the _batch_, just from its name. We fix that by renaming the
versions of the batch.
In this commit, we change the key stored within the internal order kit
into a raw pubkey array. Along the way we fix a bug in the verifier
tests due to using a map with pointer keys rather than the actual value
itself.
Previously, if the connection between the trader and auctioneer was torn
down before the trader received a batch's finalize message, then the
trader would lose all context about the batch they participated in.
Committing the batch before providing our signatures to the auctioneer
ensures that this cannot happen. Follow-up work will allow the trader to
obtain the latest information regarding a pending batch upon
reconnections.
