When add adding a project, I would like the option to add multiple projects.

When add adding a project, I would like the option to add multiple projects. I have a file with a subfoder of projects. Would be great to select many folders within the parent folder to add.

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| Field | Value |
| --- | --- |
| App version | 1.1.10 |
| OS | macOS 26.6.1 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Day 1 |

Start from the project-add flow reached from the /chat path and inspect how folder selection currently works. Done means selecting multiple project folders within one parent and adding them together on macOS; no file or test is named in the issue.

索引モデルが issue の本文から書いたものです。