fix(payment): align plate-follow cash preview with wallet balance

Use cash wallet for plate follow cashiers and stop stubbing methods when Gateway is missing.

inc/helpers/aksrt-pay.php

@@ -86,9 +86,8 @@ if (!function_exists('aksrt_list_cash_payment_methods')) {
             : ['alipay', 'wechatpay', 'paypal', 'stripe'];
 
         if (!class_exists('\AKSRT\Payment\Gateway')) {
-            return $logged_in
-                ? [['id' => 'balance', 'name' => __('站内余额', 'aksrt')]]
-                : [['id' => 'alipay', 'name' => __('支付宝', 'aksrt')]];
+            // No gateway manager → no real methods (avoid dead balance/alipay stubs).
+            return [];
         }
 
         $methods = [];

src/AKSRT/Forum/PlateFollowPay.php

@@ -188,16 +188,14 @@ class PlateFollowPay {
         }
         $has_followed = $this->user_has_followed($uid, $plate_id);
 
-        $balance = 0;
-        if ($uid > 0 && class_exists('\AKSRT\Credits\Credits')) {
-            $balance = (int) \AKSRT\Credits\Credits::balance($uid);
+        $wallet_balance = 0.0;
+        if ($uid > 0 && class_exists('\AKSRT\Credits\Balance') && \AKSRT\Credits\Balance::enabled()) {
+            $wallet_balance = (float) \AKSRT\Credits\Balance::balance($uid);
         }
 
         $methods = function_exists('aksrt_list_cash_payment_methods')
             ? aksrt_list_cash_payment_methods($uid > 0)
-            : ($uid > 0
-                ? [['id' => 'balance', 'name' => __('站内余额', 'aksrt')]]
-                : [['id' => 'alipay', 'name' => __('支付宝', 'aksrt')]]);
+            : [];
 
         $coupon_allowed = $this->is_coupon_allowed($plate_id);
         $coupon_error = '';
@@ -258,8 +256,9 @@ class PlateFollowPay {
             'need_vip' => false,
             'need_purchase' => !$has_followed && !$is_free,
             'logged_in' => $uid > 0,
-            'balance' => $balance,
-            'balance_enough' => true,
+            'balance' => $wallet_balance,
+            'wallet_balance' => $wallet_balance,
+            'balance_enough' => $is_free || ($wallet_balance + 0.0001 >= (float) $payable),
             'payment_methods' => $methods,
             'login_url' => wp_login_url(get_permalink($post)),
             'vip_url' => home_url('/'),