Add --source winget to all remaining winget install and uninstall calls

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

powershell/Winget-Remove-BuiltInApps.ps1

@@ -90,7 +90,7 @@ $Packages = @(
 foreach ($Package in $Packages) {
     Write-Host "Uninstalling: $Package" -ForegroundColor Cyan
 
-    winget uninstall --name "$Package" --silent --accept-source-agreements --nowarn
+    winget uninstall --name "$Package" --source winget --silent --accept-source-agreements --nowarn
 
     if ($LASTEXITCODE -eq 0) {
         Write-Host "$Package successfully uninstalled" -ForegroundColor Green