功能建议：支持左侧边栏折叠，以优化屏幕空间管理

[dden5767]

你好！首先我想说，AiCode 真的是一个非常惊艳的项目。我对它的完成度和设计思路感到由衷的佩服。非常感谢你投入时间和精力开发这个工具——用起来真的非常舒服，真心感谢你的付出！

我想针对目前三个主要面板（左侧：聊天/文件，中间：聊天，右侧：代码编辑器）的布局提出一个小建议。

目前，中间和右侧面板的宽度是可以调节的（可以拖动调整大小），右侧面板也可以完全隐藏。但是，左侧面板的宽度是固定的，无法相对于其他面板进行更改。

我的建议：
能否将左侧面板设为可折叠的？最好能像手风琴一样。

· 点击按钮 → 左侧面板完全折叠（隐藏）。
· 再次点击 → 左侧面板恢复到原来的状态。

这对于手机用户来说非常实用，因为这样可以在不失去快速访问聊天列表和文件的情况下，最大化屏幕空间来阅读聊天内容或查看代码。

再次感谢你的出色工作，也感谢你考虑这个建议！

Hello! I just wanted to start by saying that AiCode is an absolutely incredible project. I am genuinely impressed by how well it works and how thoughtfully it's designed. Thank you so much for all the time and effort you put into developing this — it's a real pleasure to use, and I truly appreciate your work!

I would like to suggest a small UI improvement regarding the layout of the three main panels (Left: Chats/Files, Middle: Chat, Right: Code Editor).

Currently, the width between the Middle and Right panels is adjustable (you can drag to resize), and the Right panel can be completely hidden. However, the width of the Left panel is fixed and cannot be changed relative to the other panels.

My suggestion:
Could you please make the Left panel collapsible? Ideally, like an accordion.

· Click a button → the Left panel collapses completely (hides).
· Click again → the Left panel expands back to its original state.

This would be extremely helpful for mobile users who want to maximize screen space for reading chat or viewing code, without losing quick access to their chat list and files.

Thank you again for your amazing work and for considering this suggestion!