chore(color): refactor window close / delete logic (#7804)

Co-authored-by: Peter Feerick <5500713+pfeerick@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

radio/src/lua/lua_widget.cpp

@@ -263,13 +263,12 @@ LuaWidget::LuaWidget(const WidgetFactory* factory, Window* parent,
     lv_obj_add_event_cb(lvobj, LuaWidget::redraw_cb, LV_EVENT_DRAW_MAIN,
                         nullptr);
   }
-}
 
-LuaWidget::~LuaWidget()
-{
-  luaL_unref(lsWidgets, LUA_REGISTRYINDEX, zoneRectDataRef);
-  if (errorMessage)
-    free(errorMessage);
+  onClosing([=]() {
+    luaL_unref(lsWidgets, LUA_REGISTRYINDEX, zoneRectDataRef);
+    if (errorMessage)
+      free(errorMessage);
+  });
 }
 
 void LuaWidget::onClicked()