Add getCurrentPlayer() method to ChessEngine

schach/src/main/java/de/hs_mannheim/informatik/chess/model/ChessEngine.java

@@ -83,4 +83,8 @@ public class ChessEngine {
         return board.isDraw();
     }
     
+    public String getCurrentPlayer() {
+        return board.getSideToMove().toString(); // "WHITE" oder "BLACK"
+    }
+    
 }