feat: add internal storage scale option to preferences window

src/data/settings.hpp

@@ -192,7 +192,10 @@ public:
   
   // --------------------------------------------------- : Special game stuff
   String apprentice_location;
-  
+  
+  // --------------------------------------------------- : Internal settings
+  double internal_scale;
+
   // --------------------------------------------------- : Update checking
   #if USE_OLD_STYLE_UPDATE_CHECKER
     String updates_url;