refactor: remove forum and topic feature chains

src/Core/Shortcodes.php

@@ -95,7 +95,7 @@ class Shortcodes {
     }
 
     /**
-     * [payshow]...[/payshow] — 付费后可见（文章 content-pay 或论坛主题解锁）
+     * [payshow]...[/payshow] — 文章付费后可见。
      */
     public function render_payshow(array $atts = [], string $content = ''): string {
         $atts = shortcode_atts(['message' => ''], $atts, 'payshow');
@@ -178,7 +178,7 @@ class Shortcodes {
     }
 
     /**
-     * Whether current viewer may see a paid hide block on this post/topic.
+     * Whether current viewer may see a paid hide block on this post.
      */
     private function viewer_can_see_paid_block(int $pid): bool {
         if ($pid <= 0) {