refactor(assets): vendor 资产迁入标准目录并全仓去除 zibll 标识

- assets/vendor 全量迁移: fontawesome5→assets/fontawesome5, css→assets/css,
  js→assets/js/runtime(避开 14 个同名自有文件), img 合并去重→assets/img,
  fonts→assets/fonts; 删除 assets/vendor
- libs 五个与 widgets/third-party 字节相同的库不重复入库, loader paths 改指向
- 运行时切换: _win.uri=assets 根, loader baseUrl=/js/runtime, enlighter 注入
  路径同步; PHP 7 个引用文件切换并改名 $zibll_*→$runtime_*
- 去品牌: Qinver 头注释/品牌 console.log/演示链接清除, 默认文案中性化
- 功能标识符改名: zib__→aksrt__, zib_ajax→aksrt_ajax, window.zib→
  window.aksrtLegacy, zibllblock/*→aksrtblock/*, .zib-widget→.aksrt-panel,
  .zib-slider→.aksrt-slider, zib_menu_options meta 键等
- 自有 CSS 改名: legacy-utilities/compat-vars/footer shell
- admin SPA 重建; 契约测试同步(路径/断言/文件更名)
- 例外保留: tests/visual 对照环境与 fixtures 前缀(外部 Zibll 产品引用)

验证: php -l 133 个改动文件通过; runtime 86 个 JS node --check 通过;
契约测试 68/70(2 个失败经 stash 对照确认为存量问题)

src/Settings/PaymentRuntime.php

@@ -18,7 +18,7 @@ class PaymentRuntime {
         $settings = Settings::get_all();
 
         $box_position = sanitize_key((string) ($settings['pay_box_position'] ?? 'top'));
-        // Zibll: box_top | top | bottom | box_bottom
+        // legacy: box_top | top | bottom | box_bottom
         if (!in_array($box_position, ['box_top', 'top', 'bottom', 'box_bottom'], true)) {
             $box_position = 'top';
         }
@@ -59,7 +59,7 @@ class PaymentRuntime {
     }
 
     /**
-     * Content coupon global switches (zibll coupon_post_s).
+     * Content coupon global switches (legacy coupon_post_s).
      *
      * @return array{enabled:bool,desc:string}
      */
@@ -72,7 +72,7 @@ class PaymentRuntime {
     }
 
     /**
-     * Balance recharge settings (Zibll pay_balance_* contract).
+     * Balance recharge settings (legacy pay_balance_* contract).
      *
      * @return array<string,mixed>
      */
@@ -138,7 +138,7 @@ class PaymentRuntime {
     }
 
     /**
-     * Dual-level VIP settings (Zibll pay_user_vip_1 / pay_user_vip_2).
+     * Dual-level VIP settings (legacy pay_user_vip_1 / pay_user_vip_2).
      *
      * @return array<string,mixed>
      */
@@ -344,7 +344,7 @@ class PaymentRuntime {
     }
 
     /**
-     * Order display / checkout policy (Zibll pay_* + AKSRT order ops).
+     * Order display / checkout policy (legacy pay_* + AKSRT order ops).
      *
      * @return array<string,mixed>
      */