Automatically add debug configuration when opening Blazor WASM projects in VSCode

[mkArtakMSFT]

No description provided.

[mkArtakMSFT]

This is blocked on the JS Debugger team: https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1028008

[NTaylorMullen]

Launch.json config template:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
 
        {
            "type": "pwa-chrome",
            "request": "launch",
            "name": "Launch Chrome against Blazor",
            "url": "http://localhost:8080",
            "webRoot": "${workspaceFolder}",
            "inspectUri": "{wsProtocol}://{url.hostname}:{url.port}/_framework/debug/ws-proxy?browser={browserInspectUri}"
        }
    ]
}

[NTaylorMullen]

@SteveSandersonMS @danroth27 @mkArtakMSFT I have a PR out for O#: dotnet/vscode-csharp#3593 . I haven't been able to test it end-to-end due to issues but the layout of the launch.json is there.

I'm looking for:

1. Verification the launch.json has the correct assumptions
2. A timeline for when I should merge that PR into O# to ensure it doesn't go out before we're ready