fix(zephr/ui): color picker and small mouse event fixes

- reset pressed state at the end of the frame
- correctly place the color picker regardless of window size
- make color picker popup border radius consistent regardless of window
  size
- don't draw the color picker popup if it's parent is not visible

ui.h

@@ -43,6 +43,7 @@ typedef struct Rect {
 
 typedef struct UI {
   bool popup_open;
+  UiIdHash popup_parent_hash;
   Rect popup_rect;
   UIConstraints popup_parent_constraints;
   Color *popup_revert_color;