Added migrations for contacts and started working through thread migration (have contact and closed group threads migrating)
Deprecated usage of ECKeyPair in the migrations (want to be able to remove Curve25519Kit in the future)
Added a new OpenGroupServerIdLookup to make it easier to get a database id via an open group server id
Added a migration to generate the above data
Updated the handleCompactBody method to stop early if there are no messages to delete (would previously enumerate all interactions regardless)
Updated the handleCompactBody to fetch the mapping for the deleted message so we can avoid enumerating all interactions