Add support for launching DebugProxy from `blazorwasm` debug type in VS Code

[captainsafia]

To support debugging in WSL and Codespaces, we need to move the logic that launches the DebugProxy in Blazor from our DevServer logic to the blazorwasm debug type.

To fully support remote debugging, there is some work required to add support for using a WebSocket-based transport when communicating with the browser launched over the users machine. This will be tracked in a separate issue at #29657.

[mkArtakMSFT]

@captainsafia moving these debugging related issues to RC1 but we need to re-evaluate together which ones will make it in.