feat(widgets): pricing/FAQ/stats + forum topic list and bbs sidebars

Add zibll produck widgets (pricing plans, FAQ, stats), forum topic
lists, register bbs_* sidebar zones, and wire plate/topic/home/compose
templates to render those widget areas.

src/AKSRT/Core/SetupPart1.php

@@ -382,6 +382,29 @@ trait SetupPart1 {
             'after_title'   => $title_after,
         ]);
 
+        // ── Forum / BBS widget areas (zibll bbs_* parity lite) ──
+        $forum_widgets = [
+            'bbs_home_sidebar'           => [__('论坛首页 · 侧栏', 'aksrt'), __('论坛首页侧栏区域。', 'aksrt')],
+            'bbs_home_top_fluid'         => [__('论坛首页 · 顶部全宽', 'aksrt'), __('论坛首页顶部全宽。', 'aksrt')],
+            'bbs_plate_sidebar'          => [__('论坛版块 · 侧栏', 'aksrt'), __('版块页侧栏。', 'aksrt')],
+            'bbs_plate_top_fluid'        => [__('论坛版块 · 顶部全宽', 'aksrt'), __('版块页顶部全宽。', 'aksrt')],
+            'bbs_posts_sidebar'          => [__('论坛帖子 · 侧栏', 'aksrt'), __('帖子页侧栏挂件区。', 'aksrt')],
+            'bbs_posts_top_fluid'        => [__('论坛帖子 · 顶部全宽', 'aksrt'), __('帖子页顶部全宽。', 'aksrt')],
+            'bbs_new_posts_sidebar_top'  => [__('论坛发帖 · 侧栏顶部', 'aksrt'), __('发帖页侧栏顶部。', 'aksrt')],
+            'bbs_new_posts_sidebar_bottom' => [__('论坛发帖 · 侧栏底部', 'aksrt'), __('发帖页侧栏底部。', 'aksrt')],
+        ];
+        foreach ($forum_widgets as $sid => $meta) {
+            register_sidebar([
+                'id'            => $sid,
+                'name'          => $meta[0],
+                'description'   => $meta[1],
+                'before_widget' => $card_wrapper_before,
+                'after_widget'  => '</div>',
+                'before_title'  => $title_before,
+                'after_title'   => $title_after,
+            ]);
+        }
+
         // ── Shop widget areas (§6.9) ──
         $shop_widgets = [
             'shop_product_top_fluid'    => ['商品详情页 · 顶部通栏', '商品详情页顶部全宽区域。'],