gwen: Extract conpty nupkg with tar on Windows PowerShell 5.1

script/bundle-windows.ps1

@@ -236,7 +236,10 @@ function DownloadConpty {
     $url = "https://github.com/microsoft/terminal/releases/download/v1.23.13503.0/Microsoft.Windows.Console.ConPTY.1.23.251216003.nupkg"
     $zipPath = ".\Microsoft.Windows.Console.ConPTY.1.23.251216003.nupkg"
     Invoke-WebRequest -Uri $url -OutFile $zipPath
-    Expand-Archive -Path $zipPath -DestinationPath ".\conpty" -Force
+    New-Item -Path ".\conpty" -ItemType Directory -Force
+    # Expand-Archive (PS 5.1) rejects the .nupkg extension; the file is a zip
+    # and tar.exe handles it.
+    tar -xf $zipPath -C ".\conpty"
 }
 
 function DownloadPdfium {