[Feature]: Add instructions for uninstalling vfox to the documentation

[linghengqian]

1. Your usage scenarios?

• I was just testing the difference between vfox and sdkman!.

2. What is your expected outcome?

• Although on Windows, vfox is installed as an application and therefore appears to be uninstallable via the control panel, a powshell script is also created on Windows via a command like if (-not (Test-Path -Path $PROFILE)) { New-Item -Type File -Path $PROFILE -Force }; Add-Content -Path $PROFILE -Value 'Invoke-Expression "$(vfox activate pwsh)"'.
• It would be great if the vfox documentation could record how to uninstall the vfox main program and mount the vfox shell script like https://sdkman.io/install#uninstallation . This is useful for testing reinstalling vfox.