feat(pay): sales volume, paid order meta, pending resume, limit-over buy

Bump content sales on resource order paid; show order number/time in download
box; poll pending gateway payments; support download_limit_over_price overbuy.

inc/helpers/aksrt-vip.php

@@ -270,14 +270,22 @@ if (!function_exists('aksrt_check_free_download_quota')) {
 
         $used = aksrt_get_user_free_downloaded_number($user_id);
         if ($used >= $limit) {
+            $data = [
+                'status' => 429,
+                'limit'  => $limit,
+                'used'   => $used,
+            ];
+            // Optional overbuy price for free-quota exhausted (Zibll download_limit_over_price).
+            // Callers may pass post context via filter.
+            $over = apply_filters('aksrt_download_limit_over_price', 0.0, $user_id);
+            if ($over > 0) {
+                $data['download_limit_over_price'] = $over;
+                $data['allow_limit_over'] = true;
+            }
             return new WP_Error(
                 'aksrt_download_limit',
                 __('您今日下载免费资源个数已超限，请明日再下载。', 'aksrt'),
-                [
-                    'status' => 429,
-                    'limit'  => $limit,
-                    'used'   => $used,
-                ]
+                $data
             );
         }