assistant: Remove some re-exports (#23262)

This PR removes some re-exports from the `assistant` to make it clearer
what its constituent modules depend on.

Release Notes:

- N/A
4d22f7e529Marshall Bowers committed on 1/16/2025, 10:49:14 PM· committed by GitHubparent8030c00
11 files changedLine totals unavailable