Set default CLI rasterizer to be ASCII

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

apps/wolf_3d_cli/lib/cli_game_loop.dart

@@ -24,8 +24,9 @@ class CliGameLoop {
                'engine.input',
                'CliGameLoop requires a CliInput instance.',
              ),
-       primaryRasterizer = SixelRasterizer(),
+
-       secondaryRasterizer = AsciiRasterizer(isTerminal: true) {
+       primaryRasterizer = AsciiRasterizer(isTerminal: true),
+       secondaryRasterizer = SixelRasterizer() {
     _rasterizer = primaryRasterizer;
   }