[nostalgia] Split part of Core out into Foundation, add module system

src/nostalgia/core/studio/tilesheeteditormodel.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 - 2022 Gary Talent (gary@drinkingtea.net). All rights reserved.
+ * Copyright 2016 - 2023 Gary Talent (gary@drinkingtea.net). All rights reserved.
  */
 
 #pragma once
@@ -23,7 +23,7 @@ class TileSheetEditorModel: public ox::SignalHandler {
 		static const Palette s_defaultPalette;
 		TileSheet m_img;
 		TileSheet::SubSheetIdx m_activeSubsSheetIdx;
-		AssetRef<Palette> m_pal;
+		foundation::AssetRef<Palette> m_pal;
 		studio::UndoStack m_undoStack;
 		class DrawCommand *m_ongoingDrawCommand = nullptr;
 		bool m_updated = false;