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 |

Reproduce the freeze on app version 1.1.12 on macOS 26.6.2 from /chat with an Excel document loaded to a canvas, and observe when it occurs. Done means the chat session remains usable in this scenario; the report does not identify source files, tests, or a more specific entry point.

索引モデルが issue の本文から書いたものです。