Permission prompt incorrectly associates non-git directory with CLI session's git repo when adding safe directory

### Describe the bug

Bug: When editing a file in a directory that is not under git (e.g., C:\temp\copilot), the permission prompt "Yes, and don't ask again for file operations in this repo" incorrectly references the CLI session's current git repository (C:\git\jdev\src) instead of the file's actual directory. The safe-directory association should be based on the file being edited, not the CLI's CWD.

### Affected version

You're running **GitHub Copilot CLI 1.0.56**. Worth including in your bug report!

### Steps to reproduce the behavior

start copilot in a directory that is under git control. tell copilot to create a file in a directory that is not under git control. it will ask if it can edit the file and then ask if it should put the git-controlled directory in the directories list

### Expected behavior

I would expect it to ask if it can put the directory where I've asked it to edit the file in its safe directories list.

### Additional context

_No response_

Reproduza o prompt iniciando a CLI em um diretório controlado por git e pedindo que ela crie um arquivo em um diretório não relacionado, como C:\temp\copilot. Rastreie como a escolha de safe-directory é associada ao arquivo editado e confirme que o prompt nomeia o diretório desse arquivo, e não o repositório atual da sessão da CLI.

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