This PR deletes the old `ui` and `storybook` crates in favor of their
newer variants that we'll be landing to `main` in the near future.
### Motivation
These crates are based off the old version of GPUI 2 (the `gpui2`
crate).
At this point we have since transitioned to the new version of GPUI 2
(the `gpui3` crate, currently still on the `gpui2` branch).
Having both copies around is confusing, so the old ones are going the
way of the dinosaurs.
Release Notes:
- N/A
This PR mainlines the current state of new GPUI2-based UI from the
`gpui2-ui` branch.
Release Notes:
- N/A
---------
Co-authored-by: Nate Butler <iamnbutler@gmail.com>
Co-authored-by: Max Brunsfeld <maxbrunsfeld@gmail.com>
Co-authored-by: Marshall Bowers <1486634+maxdeviant@users.noreply.github.com>
Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>
Co-authored-by: Nate <nate@zed.dev>
Co-authored-by: Mikayla <mikayla@zed.dev>
