refactor: rename event from expandChange to collapsedChange in ChatThinking component

Author: zydemail

packages/pro-components/chat/chat-thinking/README.md

@@ -63,7 +63,7 @@ collapsed | Boolean | false | 是否折叠（受控） | N
 
 名称 | 参数 | 描述
 -- | -- | --
-expand-change | `(value: Boolean)` | 展开图标点击事件。TS 类型：`TNode`。[通用类型定义](https://github.com/Tencent/tdesign-vue-next/blob/develop/packages/components/common.ts)。[详细类型定义](https://github.com/Tencent/tdesign-vue-next/blob/develop/packages/pro-components/chat/type.ts)。
+collapsedChange | `(value: Boolean)` | 展开图标点击事件。TS 类型：`TNode`。[通用类型定义](https://github.com/Tencent/tdesign-vue-next/blob/develop/packages/components/common.ts)。[详细类型定义](https://github.com/Tencent/tdesign-vue-next/blob/develop/packages/pro-components/chat/type.ts)。
 
 ### CSS Variables
 

packages/pro-components/chat/chat-thinking/_example/complete/index.js

@@ -8,7 +8,7 @@ Component({
     },
   },
   methods: {
-    handleExpandChange(e) {
+    handleCollapsedChange(e) {
       console.log('展开状态变化:', e.detail);
     },
   },

packages/pro-components/chat/chat-thinking/_example/complete/index.wxml

@@ -1,3 +1,3 @@
 <view class="chat-example-block">
-  <t-chat-thinking content="{{content}}" layout="block" status="{{status}}" bind:expandChange="handleExpandChange" />
+  <t-chat-thinking content="{{content}}" layout="block" status="{{status}}" bind:collapsedChange="handleCollapsedChange" />
 </view>

packages/pro-components/chat/chat-thinking/_example/pending/index.js

@@ -8,7 +8,7 @@ Component({
     status: 'pending',
   },
   methods: {
-    handleExpandChange(e) {
+    handleCollapsedChange(e) {
       console.log('展开状态变化:', e.detail);
     },
   },

packages/pro-components/chat/chat-thinking/_example/pending/index.wxml

@@ -1,3 +1,3 @@
 <view class="chat-example-block">
-  <t-chat-thinking content="{{content}}" layout="block" status="{{status}}" bind:expandChange="handleExpandChange" />
+  <t-chat-thinking content="{{content}}" layout="block" status="{{status}}" bind:collapsedChange="handleCollapsedChange" />
 </view>

packages/pro-components/chat/chat-thinking/chat-thinking.ts

@@ -56,7 +56,7 @@ export default class ChatThinking extends SuperComponent {
         localCollapsed: !this.data.localCollapsed,
       });
       // 通知父组件状态变化
-      this.triggerEvent('expandChange', this.data.localCollapsed);
+      this.triggerEvent('collapsedChange', this.data.localCollapsed);
     },
     setContentStyle() {
       if (this.data.maxHeight) {