Add the hair part library and give the roster three silhouettes

CHANGELOG.md

@@ -14,6 +14,8 @@ Semantic Versioning.
 - Hands, head gear and carried items were re-fitted to the new characters: hand items sit in the
   palm instead of floating at the wrist, the lanyard moved up to the sternum, back gear moved up to
   shoulder-blade height, and the clipboard is carried by its top edge.
+- NPCs no longer all share one hairstyle: the roster now uses short, buzz and long hair silhouettes
+  instead of a single shell in twelve colours.
 - Eyes now have whites and pupils instead of flat dark rectangles.
 - Every NPC now has a visible mouth; the Quaternius heads shipped without one, so the faces read as
   brow-and-eye masks.