layout: Separate button info from state

Splitting out state into a dedicated place lets keep all the immutable metadata in one place, and all state in another.

src/drawing.rs

@@ -88,7 +88,7 @@ mod c {
             let state = RefCell::borrow(&button.state).clone();
 
             let locked = LockedStyle::from_action(
-                &state.action,
+                &button.action,
                 &active_modifiers,
                 layout.get_view_latched(),
                 &layout.state.current_view,