This PR introduces a few components for the model selector pickers.
Given we're still maintaining two flavors of it due to one of them being
wired through ACP and the other through the language model registry,
having one source of truth for the UI should help with maintenance
moving forward, considering that despite the internal differences, they
look and behave the same from the standpoint of the UI.
Release Notes:
- N/A
5f054e8d9c