chore(backlog): 记录 g50 完成

.ua/backlog.json

@@ -756,6 +756,14 @@
       "acceptance": "新增 autoComplete（输入即过滤、↑↓ 环形高亮、Enter 选中、Esc 入栈、options 函数式远程联想、空态提示）；manifest/docs/demo/README/计数同步；npm run check 全绿",
       "status": "done",
       "notes": "自补：组件补充；mousedown+preventDefault 保住输入框焦点"
+    },
+    {
+      "id": "g50",
+      "title": "新增 datePicker 日期选择组件",
+      "motivation": "表单体系里日期只能填文本，缺一个受控的单月网格选择器；min/max 约束与键盘逐日导航是排期/账期场景的刚需",
+      "acceptance": "新增 datePicker（单月网格、翻月、今天、min/max 闭区间、←→↑↓/PageUp/PageDown/Enter、Esc 入栈、value 信号）；manifest/docs/demo/README/计数同步；npm run check 全绿",
+      "status": "done",
+      "notes": "自补：表单组件补缺；跨月自动翻页，漫游 tabindex 只有焦点日可 Tab 进入"
     }
   ]
 }

.ua/iterations.log

@@ -94,3 +94,4 @@
 {"ts":"2026-10-26T12:10:25+08:00","id":"g47","result":"done","commit":"d81b724","summary":"新增 cascader 级联选择：多列联动/悬停下钻/点击提交/changeOnSelect/全键盘，浏览路径与已提交路径分离，组件数 45→46"}
 {"ts":"2026-10-26T12:11:45+08:00","id":"g48","result":"done","commit":"d7bfabb","summary":"新增 splitter 可拖拽分栏：指针拖拽+方向键微调+双击复位+min 夹逼+横纵两向，组件数 46→47"}
 {"ts":"2026-10-26T12:12:56+08:00","id":"g49","result":"done","commit":"cb8a9ea","summary":"新增 autoComplete 自动补全：输入即过滤、↑↓ 环形高亮、Enter 选中、Esc 入栈、options 支持函数式远程联想，组件数 47→48"}
+{"ts":"2026-10-26T12:14:00+08:00","id":"g50","result":"done","commit":"e270e09","summary":"新增 datePicker 日期选择：单月网格+翻月/今天+min-max 闭区间+逐日逐周逐月键盘导航，组件数 48→49"}