Windows Ramdisk Directory does not exist or cannot be accessed

### Describe the bug

OS: Windows11
Node: node-v24.11.1-win-x64

When launching copilot under Ramdisk, I cannot access any directories.

When launching copilot under a non-Ramdisk environment, you can access directories normally, including those of Ramdisk.

### Affected version

after 1.0.43

### Steps to reproduce the behavior

1. Set up a Ramdisk, R:
2. Start copilot under R:
3. Have the Agent list the directory structure of any directory
4. In any non-Ramdisk directory, such as C:, start copilot
5. Have the Agent list the directory structure of any directory

### Expected behavior

Ramdisk should not be a limiting factor for copilot

### Additional context

https://sourceforge.net/projects/imdisk-toolkit/

Reproduce the directory-listing steps on Windows 11 with copilot-cli started from the R: Ramdisk and compare them with a launch from C:. The report names no source file, test, or entry point, so first trace the directory-listing path and capture the failing access behavior. Done means directories are accessible when copilot-cli starts under a Ramdisk, while the existing non-Ramdisk behavior remains working.

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