Make _take_rows & _rowid Public

Hey Lance people, I'm currently using the scanner api to allow sql predicates to be passed to form a subset index of rows that match predicate. I'm saving off the _rowid from each of these as the lookup key. This is for selected pre-filtering on metadata light columns that is followed up by _take_rows on heavy columns across the dataset. I'm doing this to enable map style torch datasets where I can't rely on sql scanner predication through the scanner being only iterable.

I'm using these privates to do that work so I don't have to manually add a global offset index in my distributed write or parse out the fragment id and offset from the _rowid in my code. Is it possible to support these privates as public so there's a guarantee of the api not breaking?

Start with the scanner API entry points for the private _take_rows and _rowid methods, then trace how callers use them for predicate filtering and row lookup. Define what public API guarantee is required and verify that both operations are exposed without requiring callers to recreate global offsets or parse fragment IDs.