Add API methods to control if armour stands can move

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

@@ -344,4 +344,21 @@ public interface ArmorStand extends LivingEntity {
          */
         ADDING;
     }
+    // Paper start
+    /**
+     * Tests if this armor stand can move.
+     *
+     * <p>The default value is {@code true}.</p>
+     *
+     * @return {@code true} if this armour stand can move, {@code false} otherwise
+     */
+    boolean canMove();
+
+    /**
+     * Sets if this armor stand can move.
+     *
+     * @param move {@code true} if this armour stand can move, {@code false} otherwise
+     */
+    void setCanMove(boolean move);
+    // Paper end
 }