[Feature] 将 stats_tab.py 中的竖直滚动视图改为标签页 / Change vertical scroll view to tab view in stats_tab.py

[SunYanbox]

描述 / Description
当前 src/console/ui/widgets/stats_tab.py 标签页内部包含了“总览”、“当前 Session 信息”、“当前 Session 工具信息”、“Sessions 列表”等多个内容区域。这些区域采用竖直滚动视图（scroll view）排列，导致信息量较大时必须通过鼠标滚动才能查看所有内容，操作不够直观，且无法快速在主要信息块之间跳转。
Currently, the src/console/ui/widgets/stats_tab.py contains multiple content sections: "Overview", "Current Session Info", "Current Session Tool Info", and "Sessions List". They are arranged in a vertical scroll view, which forces users to scroll the mouse to view all content when information is abundant. This approach is not intuitive and lacks a quick way to jump between major information blocks.

建议的改进 / Proposed Improvement
将这些内容区域从竖直滚动视图改为嵌套的标签页（tab view）。将每个主要区域（总览、当前 Session 信息、当前 Session 工具信息、Sessions 列表）分别放到独立的标签页中。这样用户只需点击标签页标题即可快速切换，无需滚动，提升信息查找效率和界面整洁度。
Change the vertical scroll view into a nested tab view. Place each major section (Overview, Current Session Info, Current Session Tool Info, Sessions List) into its own tab. This allows users to switch between sections with a single click, eliminates scrolling, and improves efficiency in finding information as well as interface cleanliness.

好处 / Benefits

• 减少滚动操作，提升用户体验 / Reduces scrolling and improves user experience
• 允许用户快速在不同信息类别间切换 / Allows quick switching between different information categories
• 界面更紧凑，易于扩展更多内容 / Makes the interface more compact and easier to extend with more content

可能的影响 / Possible Impact

• 需要重构 stats_tab.py 的布局代码 / Requires refactoring the layout code in stats_tab.py
• 确保所有原有功能（如数据实时刷新、选中状态等）在标签页形式下正常工作 / Ensure all existing functionality (real-time data refresh, selection states, etc.) works correctly under the tabbed layout

优先级 / Priority
中 / Medium