when working with excel documents specifically those that need to be loaded t...

when working with excel documents specifically those that need to be loaded to a canvas, the app suddenly freezes and the chat session becomes unusable. This might potentially be a bug but something to take a look at.

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| Field | Value |
| --- | --- |
| App version | 1.1.12 |
| OS | macOS 26.6.2 |
| Theme | Monospace |
| Path | /chat |
| Tenure | Week 12 |

在 macOS 26.6.2 上，从 /chat 进入，在 app 版本 1.1.12 中加载 Excel 文档到 canvas 后复现卡顿，并观察其何时发生。完成的标准是：在此场景下聊天会话仍可使用；报告不识别源文件、测试或更具体的入口点。

由索引模型根据 Issue 内容生成。