chore(backlog): 记录 g321 完成

.ua/backlog.json

@@ -3279,7 +3279,7 @@
     {
       "id": "g321",
       "domain": "visual",
-      "status": "open",
+      "status": "done",
       "title": "纯交互控件防误选 + 移动端点按灰闪清理",
       "motivation": "按钮 / 徽标 / 页签 / 分页 / 步骤条这类控件的文案是「动作」不是「内容」：双击或拖选会把按钮文字选中变蓝，观感割裂且打断连点（现全库只有 8 处零散 user-select，交互控件基本没盖住）；移动端浏览器默认点按灰闪（tap highlight）与令牌皮肤同层突兀，按下反馈应由 :active 态承担。",
       "acceptance": "① ui.css 全局区新增一条控件清单式 user-select: none（button/tag/badge/fab/backtop/page-btn/tab/seg-btn/step/rate-star/checkbox/radio/switch/menu-item/crumb），内容型组件（代码块 / 表格 / 描述列表 / 链接）不入选、照常可复制；② 全站 ua- 类 -webkit-tap-highlight-color: transparent，不引入任何颜色字面量；③ audit:visual / audit:contrast / audit:surface / audit:motion 全绿，npm run check 通过。",

.ua/iterations.log

@@ -365,3 +365,4 @@
 {"ts":"2026-10-27T00:59:40+08:00","id":"g318","result":"done","commit":"184406f","summary":"recipes.md 新增配方 20：stepper+formItem 句柄拼分步向导，校验拦在步间、回跳不绕过校验"}
 {"ts":"2026-10-27T01:03:39+08:00","id":"g319","result":"done","commit":"dcf470c","summary":"ua info 逗号批量：--md 片段以水平线分隔，--json 多值数组单值对象保持兼容，坏 id 报序号"}
 {"ts":"2026-10-27T01:05:52+08:00","id":"g320","result":"done","commit":"7056b62","summary":"配方 21：未读数单一来源派生，静态快照组件统一 effect+replaceChildren 接信号，badge 语义交给外层 button"}
+{"ts":"2026-10-27T01:08:42+08:00","id":"g321","result":"done","commit":"0e7aca6","summary":"17 类纯交互控件 user-select:none 全局收口，ua- 类 tap-highlight 透明；内容型组件保持可复制"}