The UI needs to have the ability to split into multiple windows due to not fi...

The UI needs to have the ability to split into multiple windows due to not fitting into one large screen. If i open all panels, having sidebar open, having chat pane open, having file tree and file open it all gets very tight. Having the right side panel being able to be open in a new window (able to move to a secondary monitor) would help alot.

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| Field | Value |
| --- | --- |
| App version | 1.1.14 |
| OS | Windows 10.0.26100 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 15 |

Start at the /chat entry point and review how the sidebar, chat pane, file tree, file view, and right-side panel are composed. Clarify the multi-window behavior and secondary-monitor expectations, then define acceptance checks for opening the right panel separately while the existing panels remain usable on Windows.

索引モデルが issue の本文から書いたものです。