feat(payment): finish Zibll key contract and wire checkout gateways

Drop dual-read payment runtime fallbacks, align PHP schema to Vue keys,
read gateway credentials only from aksrt_settings with enable toggles,
expose configured adapters at checkout, fix credits pay signatures, and
apply order expiry settings. Wire orphan order/card-pass/withdrawal
schema pages; delete unused Payment* wrappers.

inc/classes/gateways/class-aksrt-wechatpay-gateway.php

@@ -20,6 +20,10 @@ class AKSRT_WechatPay_Gateway implements AKSRT_Payment_Gateway_Interface {
     }
 
     public function is_configured(): bool {
+        if (class_exists('AKSRT_Settings_Payment_Runtime')
+            && !AKSRT_Settings_Payment_Runtime::is_gateway_enabled('wechatpay')) {
+            return false;
+        }
         $config = $this->get_config();
         return !empty($config['mch_id']) && !empty($config['key']);
     }
@@ -206,24 +210,19 @@ class AKSRT_WechatPay_Gateway implements AKSRT_Payment_Gateway_Interface {
     }
 
     private function get_config(): array {
-        // 优先从统一设置读取（schema 保存的 key）
-        if (class_exists('AKSRT_Settings')) {
-            $all = AKSRT_Settings::get_all();
-            if (!empty($all['wechat_merchantid'])) {
-                return [
-                    'mch_id'     => $all['wechat_merchantid'] ?? '',
-                    'key'        => $all['wechat_jsapi'] ?? '',
-                    'appid'      => $all['wechat_appid'] ?? '',
-                    'appsecret'  => $all['wechat_appsecret'] ?? '',
-                    'cert_path'  => $all['wechat_cert_path'] ?? '',
-                    'key_path'   => $all['wechat_key_path'] ?? '',
-                    'payment_type' => $all['wechat_payment_type'] ?? 'native',
-                ];
-            }
+        if (!class_exists('AKSRT_Settings')) {
+            return [];
         }
-        // 回退到独立 option
-        $settings = get_option('aksrt_payment_wechatpay', []);
-        return is_array($settings) ? $settings : [];
+        $all = AKSRT_Settings::get_all();
+        return [
+            'mch_id'        => (string) ($all['wechat_merchantid'] ?? ''),
+            'key'           => (string) ($all['wechat_jsapi'] ?? ''),
+            'appid'         => (string) ($all['wechat_appid'] ?? ''),
+            'appsecret'     => (string) ($all['wechat_appsecret'] ?? ''),
+            'cert_path'     => (string) ($all['wechat_cert_path'] ?? ''),
+            'key_path'      => (string) ($all['wechat_key_path'] ?? ''),
+            'payment_type'  => (string) ($all['wechat_payment_type'] ?? 'native'),
+        ];
     }
 
     private function create_sdk(array $config): \Yurun\PaySDK\Weixin\SDK {