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.

src/AKSRT/User/Center.php

@@ -73,6 +73,12 @@ class Center {
                 'priority' => 50,
                 'type'     => 'panel',
             ],
+            'vip' => [
+                'label'    => __('我的会员', 'aksrt'),
+                'icon'     => 'crown',
+                'priority' => 45,
+                'type'     => 'panel',
+            ],
             'notif' => [
                 'label'    => __('消息通知', 'aksrt'),
                 'icon'     => 'bell',
@@ -119,12 +125,26 @@ class Center {
             $this->panels['credits'] = $panel;
         }
 
+        // Dedicated VIP tab when membership is enabled.
+        $vip_on = class_exists('\AKSRT\Settings\Settings')
+            && !empty(\AKSRT\Settings\Settings::get_payment_vip_settings()['enabled']);
+        if ($vip_on && !isset($this->panels['vip'])) {
+            $this->panels['vip'] = $definitions['vip'];
+        } elseif (!$vip_on && isset($this->panels['vip'])) {
+            unset($this->panels['vip']);
+        }
+
         if (!isset($this->panels['settings'])) {
             $this->panels['settings'] = $definitions['settings'];
         }
 
         $this->panels['notif'] = $definitions['notif'];
 
+        // Keep stable order by priority.
+        uasort($this->panels, static function (array $a, array $b): int {
+            return ((int) ($a['priority'] ?? 100)) <=> ((int) ($b['priority'] ?? 100));
+        });
+
         /**
          * 允许插件/子主题注册额外面板
          *