chore: add docs

content/start/changelog/index-en-US.md

@@ -24,6 +24,7 @@ Version：Major.Minor.Patch (follow the **Semver** specification)
   - Select、Cascader、Input、InputNumber、TreeSelect、AutoComplete、Datepicker、TImepicker add clearIcon, allow override default clear icon,  [#1309 ](https://github.com/DouyinFE/semi-design/issues/1309)
   - Cascader、Select、DatePicker、TimePicker、TreeSelect add dropdownMargin ，Dropdown、Popover add margin ，use same as tooltip margin
   - The TimePicker component whose type is timeRange supports passing in panelHeader and panelFooter in array format to set different headers and bottoms. https://github.com/DouyinFE/semi-design/issues/1316 [@zk8080](https://github.com/zk8080)
+  - TreeSelect adds a position parameter to control the direction of the pop-up layer 
 - 【Style】
   - Tag close button add hover and active color
   - Optimize the display method of Tag when the content exceeds the length, and automatically omit it  [@SyMind](https://github.com/SyMind)

content/start/changelog/index.md

@@ -25,6 +25,7 @@ Semi 版本号遵循 **Semver** 规范（主版本号-次版本号-修订版本
   - Select、Cascader、Input、InputNumber、TreeSelect、AutoComplete、Datepicker、TimePicker 增加 clearIcon，允许覆盖清除按钮,  [#1309 ](https://github.com/DouyinFE/semi-design/issues/1309)
   - Cascader、Select、DatePicker、TimePicker、TreeSelect 增加 dropdownMargin 配置，Dropdown、Popover增加 margin 配置，作用同 tooltip margin
   - type为timeRange的TimePicker组件，支持传入数组格式的panelHeader和panelFooter来设置不同的头部和底部。https://github.com/DouyinFE/semi-design/issues/1316 [@zk8080](https://github.com/zk8080)
+  - TreeSelect增加 position参数控制弹出层方向 
 - 【Style】
   - Tag 关闭按钮增加 hover 态和 active 态颜色
   - 优化 Tag 在内容超出长度时的展示方式，自动省略  [@SyMind](https://github.com/SyMind)