improve dialog browse, wrap ui task for every Node method that modifies the children list, update the ui every time the scene tree changes, restore fps and stylus state on win, fix bucket tool, fix snapshop restore, init in ui thread

src/util.h

@@ -51,6 +51,9 @@ bool point_in_rect(const glm::vec2& point, const glm::vec4& rect);
 glm::vec4 rect_intersection(glm::vec4 a, glm::vec4 b);
 // params and returns {origin, size} form
 glm::vec4 rect_union(glm::vec4 a, glm::vec4 b);
+// return the are of the box {min, max}
+float box_area(glm::vec4 b);
+glm::vec2 box_size(glm::vec4 b);
 // params and returns {min, max} form
 glm::vec4 box_union(glm::vec4 a, glm::vec4 b);
 // params and returns {min, max} form