Move getItemInUse up to LivingEntity

By: md_5 <git@md-5.net>

paper-api/src/main/java/org/bukkit/entity/LivingEntity.java

@@ -196,6 +196,16 @@ public interface LivingEntity extends Attributable, Damageable, ProjectileSource
      */
     public void setMaximumAir(int ticks);
 
+    /**
+     * Gets the item that the player is using (eating food, drawing back a bow,
+     * blocking, etc.)
+     *
+     * @return the item being used by the player, or null if they are not using
+     * an item
+     */
+    @Nullable
+    public ItemStack getItemInUse();
+
     /**
      * Gets the number of ticks remaining for the current item's usage.
      *