移除不准确的 feedCount 和 shareCount 字段，新增用户主页入口

- 删除 UserProfile.feedCount（tab 选择器已失效，改用 feeds.length 展示）
- 删除 FeedDetail.shareCount（实际无法获取分享数）
- 用户信息栏新增"主页"按钮，点击查看当前登录用户主页
- extractInitialState 补充 userProfile/homeFeed/explore key 提取

src/platforms/xiaohongshu/selectors.ts

@@ -72,7 +72,6 @@ export const XHS_SELECTORS = {
     /** Comment count. */
     commentCount: '.engage-bar .chat-wrapper .count',
     /** Share count. */
-    shareCount: '.engage-bar .share-wrapper .count',
     /** Publish / create time text. */
     createTime: '.note-scroller .bottom-container .date',
     /** IP location. */
@@ -122,8 +121,6 @@ export const XHS_SELECTORS = {
     ipLocation: '.user-info .user-ip',
     /** Follower / following / interaction count elements. */
     followCount: '.user-info .user-interactions > div',
-    /** Note count (displayed somewhere on the profile page). */
-    noteCountTab: '.reds-tab-item',
     /** Individual feed items on the user profile. */
     feedItem: '.feeds-container .note-item',
   },