add compound launch.json configurations

[aldevv]

Problem Statement

https://code.visualstudio.com/Docs/editor/debugging#_compound-launch-configurations

Possible Solutions

No response

Considered Alternatives

No response

[mfussenegger]

Depends on #586

[magoerlich]

👍 on this and #586 seems to be solved.
So, will this be implemented?

[mfussenegger]

There's now a DapNew command that can start many sessions at once: #1243

I also had a look at implementing compounds but I got the impression that the complexity is not worth it.
The implementation is either a hack but contained, or spreads quite a bit throughout the code base.

I'd rather use up the complexity budget for other features. I might change my mind about this at some point but for now I'm closing this.