Add character count support for countType: "words" using Intl.Segmenter

Author: colinrotherham

packages/nhsuk-frontend/src/nhsuk/components/character-count/character-count.mjs

@@ -477,7 +477,12 @@ export class CharacterCount extends ConfigurableComponent {
       return segments.length
     },
     words(text) {
-      return text.split(this.separator).filter(Boolean).length
+      if (!this.segmenter || 'maxwords' in this.config) {
+        return text.split(this.separator).filter(Boolean).length
+      }
+
+      const segments = Array.from(this.segmenter.segment(text))
+      return segments.filter((segment) => segment.isWordLike).length
     }
   })