Enable option to turn on mouselook

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

apps/wolf_3d_gui/lib/screens/difficulty_screen.dart

@@ -35,6 +35,7 @@ class _DifficultyScreenState extends State<DifficultyScreen> {
           difficulty: difficulty,
           startingEpisode: widget.wolf3d.activeEpisode,
           audio: widget.wolf3d.audio,
+          input: widget.wolf3d.input,
         ),
       ),
     );