Centralize retained message dialog close callbacks

src/node_message_box.cpp

@@ -1,5 +1,6 @@
 #include "pch.h"
 #include "log.h"
+#include "legacy_ui_overlay_services.h"
 #include "node_message_box.h"
 #include "layout.h"
 
@@ -23,7 +24,7 @@ void NodeMessageBox::init()
             on_submit(this);
     };
     btn_cancel = find<NodeButton>("btn-cancel");
-    on_submit = btn_cancel->on_click = [&](Node*) { destroy(); };
+    on_submit = btn_cancel->on_click = pp::panopainter::legacy_destroy_node_callback(*this);
     m_capture_children = false; // don't capture children events on mouse_capture
 }