Merge dom and component focus (#978)

Instead of two levels of focus with `focus` and `selected`, use a recursive
level. The components set the one "active" and hbox/vbox/dbox 

Co-authored-by: ArthurSonzogni <sonzogniarthur@gmail.com>

examples/component/CMakeLists.txt

@@ -18,6 +18,7 @@ example(focus_cursor)
 example(gallery)
 example(homescreen)
 example(input)
+example(input_in_frame)
 example(input_style)
 example(linear_gradient_gallery)
 example(maybe)
@@ -38,8 +39,8 @@ example(radiobox)
 example(radiobox_in_frame)
 example(renderer)
 example(resizable_split)
-example(selection)
 example(scrollbar)
+example(selection)
 example(slider)
 example(slider_direction)
 example(slider_rgb)