feat(vip): Batch 3 dedicated user-center VIP tab

Register 我的会员 panel, zibll-style status/equity cards, sidebar deep-link,
and slim credits-tab entry so VIP is no longer nested only under assets.

inc/helpers/aksrt-vip.php

@@ -407,10 +407,10 @@ function aksrt_get_vip_info(int $user_id = 0): array {
 if (!function_exists('aksrt_get_vip_purchase_url')) {
     function aksrt_get_vip_purchase_url(): string {
         if (function_exists('aksrt_get_user_center_tab_url')) {
-            return aksrt_get_user_center_tab_url('credits');
+            return aksrt_get_user_center_tab_url('vip');
         }
         if (function_exists('aksrt_get_user_center_url')) {
-            return aksrt_get_user_center_url();
+            return aksrt_get_user_center_url('vip');
         }
         return home_url('/');
     }