This commit adds the full bbolt-backed client database as well as a set
of unit tests to assert that it exactly implements the same behavior as
the mock ClientDB.
A ClientChanSummary will be inserted for each channel registered with
the client, which for now will just track the sweep pkscript to use. In
the future, this will be extended with additional information to enable
the client to efficiently compute which historical states need to be
backed up under a given policy.
In advance of the upcoming wtdb.ClientDB, we'll modify the behavior
of the mockdb to be more like the final bbolt backed one, and assert
that all or our tests are still passing.
This commit replaces the map-based CommittedUpdates field with a slice.
When reading from disk, these will already be sorted by bbolt, so the
client restore the updates as presented without needing to sort them
first.
Since the key in the map variant was the sequence number, we refactor
the CommittedUpdate struct to have a sequence number and an embedded
CommittedUpdateBody (which is equivalent to the old CommittedUpdate).
The database is then expected to populate the sequence number from the
key on disk.
Since the sequence number is now directly integrated in the
CommittedUpdate struct, this allow allows us to remove the now redundant
seqNum argument from CommitUpdate.
This commit renames the variables dbName to towerDBName and dbVersions
to towerDBVersions, to distinguish between the upcoming clientDBName
clientDBVersions. We also move resusable portions of the database
initialization and default endianness to its own file so that it can be
shared between both tower and client databases.
