Only update scrubber if not currently dragging

lib/luavgl/src/lvgl.lua

@@ -1098,6 +1098,11 @@ end
 function slider:value()
 end
 
+--- get whether slider is dragged or not
+--- @return boolean
+function slider:is_dragged()
+end
+
 ---
 --- Switch widget
 ---@class Switch:Object

lib/luavgl/src/widgets/slider.c

@@ -73,9 +73,19 @@ static int luavgl_slider_tostring(lua_State *L) {
   return 1;
 }
 
+static int luavgl_slider_is_dragged(lua_State *L) {
+  lv_obj_t *obj = luavgl_to_obj(L, 1);
+  bool is_dragged = lv_slider_is_dragged(obj);
+  lv_group_t * g   = lv_obj_get_group(obj);
+  bool editing     = lv_group_get_editing(g);
+  lua_pushboolean(L, editing || is_dragged);
+  return 1;
+}
+
 static const luaL_Reg luavgl_slider_methods[] = {
     {"set", luavgl_slider_set},
     {"value", luavgl_slider_value},
+    {"is_dragged", luavgl_slider_is_dragged},
     {NULL, NULL},
 };