feat(pay): alone download page, free-login gate, list pay badges

inc/helpers/aksrt-pay.php

@@ -328,6 +328,45 @@ if (!function_exists('aksrt_get_download_cost')) {
     }
 }
 
+/**
+ * URL of the Zibll-style single-post download page (page template + ?post=ID).
+ */
+if (!function_exists('aksrt_get_single_download_page_url')) {
+    function aksrt_get_single_download_page_url($post = null): string {
+        $p = get_post($post);
+        if (!($p instanceof WP_Post)) {
+            return '';
+        }
+
+        $page_url = '';
+        if (function_exists('aksrt_find_template_page')) {
+            $page = aksrt_find_template_page('templates/pages/page-download-file.php');
+            if ($page instanceof WP_Post) {
+                $page_url = get_permalink($page);
+            }
+        }
+        if ($page_url === '') {
+            // Fallback: look for any page using the template via slug convention.
+            $page_url = home_url('/download-file/');
+        }
+
+        return add_query_arg('post', (int) $p->ID, $page_url);
+    }
+}
+
+/**
+ * Whether independent download page mode is enabled (Zibll down_alone_page).
+ */
+if (!function_exists('aksrt_is_download_alone_page_enabled')) {
+    function aksrt_is_download_alone_page_enabled(): bool {
+        if (!class_exists('AKSRT_Settings')) {
+            return false;
+        }
+        $paid = AKSRT_Settings::get_paid_content_settings();
+        return !empty($paid['down_alone_page']) || !empty($paid['download']['alone_page']);
+    }
+}
+
 // ============================================================
 // 价格显示
 // ============================================================