chore: added Unicode utility class

Author: quintesse

twinkle-ansi/src/main/java/org/codejive/twinkle/util/Unicode.java

@@ -0,0 +1,13 @@
+package org.codejive.twinkle.util;
+
+public class Unicode {
+    public static int visibleWidth(CharSequence text) {
+        int width = 0;
+        SequenceIterator si = SequenceIterator.of(text);
+        while (si.hasNext()) {
+            si.next();
+            width += si.width();
+        }
+        return width;
+    }
+}