fix(msi): correct CustomAction pattern for elements\ read-only

- Use SetProperty + WixQuietExec two-step pattern to pass runtime
  INSTALLDIR to a deferred CustomAction (fixes WIX1077 and WIX0400)
- Add WixToolset.Util.wixext/7.0.0 extension (required for WixQuietExec)
- Fix condition syntax: collapse multi-line conditions to single line
- Add -ext WixToolset.Util.wixext to wix build command in windows-msi.yml

.github/workflows/windows-msi.yml

@@ -92,6 +92,7 @@ jobs:
           echo $toolsPath >> $env:GITHUB_PATH
           wix eula accept wix7
           wix extension add WixToolset.UI.wixext/7.0.0
+          wix extension add WixToolset.Util.wixext/7.0.0
           Write-Host "WiX v7 installed, EULA accepted, UI extension added."
 
       # ----------------------------------------------------------------
@@ -208,6 +209,7 @@ jobs:
             -d "FilesDir=$filesDir" `
             -d "LicenseRtf=$licRtf" `
             -ext WixToolset.UI.wixext `
+            -ext WixToolset.Util.wixext `
             -o "dist\$outputName"
 
           if (-not (Test-Path "dist\$outputName")) {