Button2 – Part1 (#3420)

## TODO

- [x] Remove `InteractionState`
- [ ] `Selectable` should use `Selection` instead of a boolean
- [x] Clean out ui2 prelude
- [ ] Build out button2 button types
- [ ] Port old buttons

Release Notes:

- N/A

---------

Co-authored-by: Marshall Bowers <1486634+maxdeviant@users.noreply.github.com>

crates/workspace2/src/toolbar.rs

@@ -3,7 +3,7 @@ use gpui::{
     div, AnyView, Div, Entity, EntityId, EventEmitter, ParentElement as _, Render, Styled, View,
     ViewContext, WindowContext,
 };
-use theme2::ActiveTheme;
+use ui::prelude::*;
 use ui::{h_stack, v_stack, Button, Color, Icon, IconButton, Label};
 
 pub enum ToolbarItemEvent {