Part of #1266
This is a draft of the core API + data store changes.
It's still a large PR, apologies.
The "as rows" commit could be split out, but this takes it to ~all of
the breaking changes we can't hide behind updating internals.
Same for the claimlock, but in both cases it seems these are worth
understanding when considering the API shape.
They're loadbearing for performance once we actually have multi-actor
workers.
Benjamin Elder
2c429a9906