[Requests and ideas] Hope to support adding a subfolder of a folder managed by git

**Mood**: 😊
**Category**: Requests and ideas

Hope to support adding a subfolder of a folder managed by git
Background: For monorepo, one git manages multiple sub-projects (such as iOS/Android). For an iOS developer, he only cares about iOS projects. But currently if I just want to add the iOS folder to the github copilot app, the actual effect is to add the root directory of the monorepo, which is too big.

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| Field | Value |
| --- | --- |
| App version | 0.2.33 |
| OS | macOS 26.5.1 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Day 1 |

Start by tracing how the app currently adds folders managed by Git and how it determines the repository root. Define the selection behavior for a subfolder in a monorepo, including what should happen when the user adds the iOS folder, and verify that only the selected project scope is used.

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