introduce bitloops

src/test/java/puzzle/ExportFormatTest.java

@@ -28,11 +28,11 @@ public class ExportFormatTest {
       grid.setClue(0, (byte) '2');
       // This creates a slot starting at (0,1)
       
-      var clueMap = new HashMap<Integer, Lemma>();
+      var clueMap = new HashMap<Integer, Long>();
       // key = (cellIndex << 4) | direction
       var key   = (0 << 4) | 2;
       var lemma = new Lemma("TEST");
-      clueMap.put(key, lemma);
+      clueMap.put(key, lemma.word());
       
       // Manually fill the grid letters for "TEST" at (0,1), (0,2), (0,3), (0,4)
       grid.setByteAt(Grid.offset(0, 1), (byte) 'T');