search: repurpose debug dataset as honeycomb search-zoekt

Created by: keegancsmith

It would be useful to have the detailed honeycomb logging we added for debugging OOMs always on. This promotes it to it's own dataset.

This PR is a series of mechanical refactors. Highlights:

1. remove before event
2. rename honeycomb event to search-zoekt
3. always enable if honeycomb is enabled.
4. add in logging for new stat fields