add grids panel

engine/app.h

@@ -30,6 +30,7 @@
 #ifdef __ANDROID__
 #include "main.h"
 #endif
+#include "node_panel_grid.h"
 
 class App
 {
@@ -59,6 +60,7 @@ public:
     std::shared_ptr<NodePanelLayer> layers;
     std::shared_ptr<NodePanelColor> color;
     std::shared_ptr<NodePanelStroke> stroke;
+    std::shared_ptr<NodePanelGrid> grid;
     std::shared_ptr<NodePanelBrushPreset> presets;
     NodeCanvas* canvas;
     Node* current_panel = nullptr;