api: add isFollower to NPCComposition

runelite-api/src/main/java/net/runelite/api/NPCComposition.java

@@ -96,4 +96,11 @@ public interface NPCComposition extends ParamHolder
 	 * Gets the displayed overhead icon of the NPC.
 	 */
 	HeadIcon getOverheadIcon();
+
+	/**
+	 * If the npc is a follower, such as a pet. Is affected by the
+	 * "Move follower options lower down" setting.
+	 * @return
+	 */
+	boolean isFollower();
 }