[Enhancement] GUI does not display git stderr when repository ownership is dubious

[gadfly3173]

When accessing a Git repository located inside WSL2 (e.g., via \\wsl.localhost\Ubuntu-24.04\home\...\myrepo) using Git on Windows, Git may output an error like:

fatal: detected dubious ownership in repository at '//wsl.localhost/Ubuntu-24.04/home/gadfly/Documents/sourcegit'
To add an exception for this directory, call:

	git config --global --add safe.directory '%(prefix)///wsl.localhost/Ubuntu-24.04/home/gadfly/Documents/sourcegit'

However, the GUI client does not display this stderr output , leaving users confused about why Git operations fail.

Suggested Fix

Show the stderr content from QueryLocalChanges.

[love-linger]

BTW. there're two recommended ways to use SourceGit in WSL:

1. Install SourceGit in Linux(WSL) instead of Windows. This will bring many benefits, such as: file/directory dialogs that are more compatible with the operating system, correct execution of Hooks scripts, etc.
2. Move repositories to Windows filesystem, and use /mnt/<driver>/<path_to_repo> to locate this repo in Linux(WSL).

[love-linger]

Merged.