Tile outlines on floors, wall tops and wall corners (toggle with G)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/main.rs

@@ -101,6 +101,9 @@ async fn main() {
         if (is_key_pressed(KeyCode::P) || is_key_pressed(KeyCode::Space)) && game.state == 0 {
             game.paused = !game.paused;
         }
+        if is_key_pressed(KeyCode::G) {
+            r3d.outlines = !r3d.outlines;
+        }
         if is_key_pressed(KeyCode::M) {
             sounds.muted = !sounds.muted;
         }