fix othello player skip logic

src/game.rs

@@ -53,7 +53,11 @@ impl Game {
                 }
             } else {
                 println!("Player {} did not make a move!", player_i);
-                // TODO! break, player should not be able to skip a move
+                // players are able to skip a move if they have no valid moves to make
+                assert!(
+                    !self.board.possible_moves(player_color).any(|_| true),
+                    "Player skipped a move, but they had a possible move to make"
+                );
                 return; // No valid move available
             }
         }