feat(forum,admin): plate follow-pay MVP, sales column, order type tabs

Wire paid plate follow (admin meta + points/balance purchase + AJAX),
re-check plate gate on topics, post list sales column, and order type
subtabs; update gap matrix and admin IA map.

inc/classes/forum/topic-service-traits/trait-aksrt-forum-topic-service-part-3.php

@@ -166,6 +166,14 @@ trait AKSRT_Forum_Topic_Service_Part_3 {
             return true;
         }
 
+        // Plate gate first (zibll plate → post). Moderators of plate already pass can_view_plate.
+        $plate_id = (int) get_post_meta((int) $post->ID, '_aksrt_plate_id', true);
+        if ($plate_id > 0 && method_exists($this->forum, 'can_view_plate')) {
+            if (!$this->forum->can_view_plate($viewer_user_id, $plate_id)) {
+                return false;
+            }
+        }
+
         if ($visibility === AKSRT_Forum::VISIBILITY_PUBLIC) {
             return true;
         }