New method getCurrentMoveIndex in ChessEngine

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

@@ -102,6 +102,8 @@ public class ChessEngine {
         currentMoveIndex = idx;
     }
     
+    public int getCurrentMoveIndex() { return currentMoveIndex; }
+    
     private PieceDTO convertPieceToDTO(Piece piece) {
         if (piece == null || piece.equals(Piece.NONE)) return null;
         String color = piece.name().startsWith("WHITE") ? "WHITE" : "BLACK";