R1:c21be4849f8d

By default, do not save queries when executing Conduit "*.search" calls

Summary:
Fixes T11304. Prior to this change, we did an unnecessary write on every "*.search" call (this write didn't always actually write a row, since we only save //unique// saved queries, but still doesn't do anything useful ever, currently).

Instead, change this to not-write by default. We could add an "oh, and also I want you to do a write" option later, which would let us implement something like `arc query-stuff` which says…