Unified game screen and abstracted input

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

apps/wolf_3d_gui/lib/screens/difficulty_screen.dart

@@ -32,12 +32,6 @@ class _DifficultyScreenState extends State<DifficultyScreen> {
           startingEpisode: Wolf3d.I.activeEpisode,
           audio: Wolf3d.I.audio,
         ),
-        // builder: (_) => WolfFlutterRenderer(
-        //   Wolf3d.I.activeGame,
-        //   difficulty: difficulty,
-        //   startingEpisode: Wolf3d.I.activeEpisode,
-        //   audio: Wolf3d.I.audio,
-        // ),
       ),
     );
   }