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/ui2/src/ui2.rs

@@ -12,13 +12,19 @@
 #![doc = include_str!("../docs/building-ui.md")]
 #![doc = include_str!("../docs/todo.md")]
 
+mod clickable;
 mod components;
+mod fixed;
 pub mod prelude;
+mod selectable;
 mod styled_ext;
 mod styles;
 pub mod utils;
 
+pub use clickable::*;
 pub use components::*;
+pub use fixed::*;
 pub use prelude::*;
+pub use selectable::*;
 pub use styled_ext::*;
 pub use styles::*;