also:
- removed `impl default for connectionid`, i want to be explicit about using zero.
- renamed or re-documented many uses of the word "address" which were actually referring
to the database identity, despite the concept of the database identity not having
changed in this PR.
- removed client address query param from call HTTP API
- added warn log to connection id param in subscribe HTTP API so users don't do it
- removed `client_address` from `MetadataFile`. It seemed to be unused, and I have no clue
what it would possibly be for.
- rust SDK is still supplying connection id to subscribe. this needs to change, but
inconvenient.
- C# `CallerIdentity` renamed to `Sender`, per tyler's request
Expected to be in a very broken state right now, but I'm stepping away for a moment and
wanted to save what I had so far.
Phoebe Goldman