Please add "Artifacts" as a tab on the right hand pane.

Please add "Artifacts" as a tab on the right hand pane. I can see files in the repo, but when I have a big research project the app creates a lot of artifacts, but I have to open each one individually from the button at the bottom of the left pane. It would be much better to have an artifacts tab in the right pane, which had a tree view of files etc. and let me browse more easily

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| Field | Value |
| --- | --- |
| App version | 1.1.4 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 8 |

Start in the /chat view and inspect the existing artifact-opening button at the bottom of the left pane, along with the right-hand pane's current tabs and file browsing behavior. Add an Artifacts tab with a tree view that lets users browse and open generated artifacts without opening each one individually; verify it works for projects containing many artifacts.

索引モデルが issue の本文から書いたものです。