Allow modules to support full URI paths for executable commands (e.g. custom git path)

[kvnxiao]

Feature Request

This is a feature request to support full URI paths for executable commands. In my case, I am using starship prompt on Windows and would also like to use it with zsh via msys2. However, there is an issue with msys2 when git-for-windows (via mingw64) is installed and being used, in that the terminal emulator will freeze and not accept keyboard input after resizing the window.

Is your feature request related to a problem? Please describe.

The issue illustrated: msys2/MSYS2-packages#2820

This can be worked-around by also installing a msys2 version of git and only using that version for creating terminal prompts such as git branch and status, etc., while the main git-for-windows is still used for regular git commands.

Describe the solution you'd like

It would be great if the context.exec_cmd("git", ...); calls in all the git modules could be further enhanced to support a custom executable name via the .toml config, e.g.:

[git]
git_executable = "/usr/bin/msys2_git" # default to git_executable = "git"

This can be further extended to apply to all modules for specifying the module's executable command.

Describe alternatives you've considered

N/A

Installing zsh via WSL2 on Windows is not a valid solution for me because of the IO issues when dealing with project files on the Windows filesystem (/mnt/...)