Unfortunately there's no way to run scripts after install/uninstall a VSIX:
Look at this MSDN if you search for "Configuration during install" you will read it's not supported by VSIX but only by MSI. I don't think in Vs2012 this has changed. Howver I'm running into the same problem, I opted for this solution:
public sealed class YourPackage : Package
{
protected override void Initialize()
{
base.Initialize();
var dte = (DTE2)GetService(typeof(SDTE));
_dteEvents = dte.Events.DTEEvents;
_dteEvents.OnStartupComplete += OnStartupComplete;
_dteEvents.OnBeginShutdown += OnBeginShutdown;
}
private void OnBeginShutdown()
{
_dteEvents.OnBeginShutdown -= OnBeginShutdown;
_dteEvents = null;
//Run your script
}
private void OnStartupComplete()
{
_dteEvents.OnStartupComplete -= OnStartupComplete;
_dteEvents = null;
//Run your script
}
}
it won't be as neat as a powershell script that run once, but it's a solution.
Hope it helps.