Installer doesn't always install WebView2

[ButterscotchV]

The installer doesn't seem to always install WebView2.

It seems that sometimes running the WebView2 installer from https://developer.microsoft.com/en-us/microsoft-edge/webview2/consumer/ as an administrator is still required after running the SlimeVR installer in some cases. I can't reproduce this, but iirc I've had it myself and I've seen numerous cases of this in the support channels.

Relevant support posts potentially exhibiting this issue:

• https://discord.com/channels/817184208525983775/1053904692570247198
• https://discord.com/channels/817184208525983775/1049693077704544328
• https://discord.com/channels/817184208525983775/1046847180201271377
• https://discord.com/channels/817184208525983775/878727840118505533/1057525462508769291
• https://discord.com/channels/817184208525983775/878727840118505533/1058603308333420584

[ButterscotchV]

It would seem that this issue may be caused by detection of WebView2 rather than a problem with installation of it? Is there any way we can detect if it is installed but wouldn't work for launching the GUI and needs to be installed using the installer?