fix: make WebView2 MSI bootstrap controllable

docs/install/windows.md

@@ -116,6 +116,32 @@ If an install to a local non-C: drive fails anyway, capture a log with
 [open an issue](https://github.com/debpalash/VoiceStudio/issues) with it
 — that log shows exactly which step rolled back.
 
+## Managed WebView2 installation
+
+The MSI checks both the machine-wide and current-user Edge Update registry
+keys for the WebView2 Runtime product
+`{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}`. When neither key is present, the
+default install downloads Microsoft's bootstrapper from
+`https://go.microsoft.com/fwlink/p/?LinkId=2124703` with PowerShell and runs it
+silently with `/install`.
+
+Managed or offline deployments can prohibit that network action:
+
+```powershell
+msiexec /i VoiceStudio*.msi DISABLEWEBVIEW2BOOTSTRAP=1 AUTOLAUNCHAPP=0 /qn /L*V install.log
+```
+
+With `DISABLEWEBVIEW2BOOTSTRAP=1`, detection still runs but no WebView2
+PowerShell, download, or installer action can start. If the runtime is absent,
+the MSI fails before copying VoiceStudio and tells the operator to deploy the
+[Microsoft Evergreen Standalone Runtime](https://developer.microsoft.com/microsoft-edge/webview2/#download-section)
+first. This fail-closed behavior prevents a detection miss from becoming an
+unexpected elevated download. `/L*V` records detection and action selection in
+the named Windows Installer log.
+
+`AUTOLAUNCHAPP=0` is independent: it prevents VoiceStudio from launching after
+a successful silent install. It does not disable WebView2 detection or setup.
+
 ## Portable install (Windows)
 
 <a id="portable-install"></a>