Make the profile selection less confusing to users

[billti]

In the past 24 hours we've had 2 'bug reports' that were 'by design' due to how choosing between 'base' and 'unrestricted' profiles works (#1195 and #1196 ). Seems like we have some user experience work to do here to make this more intuitive and friendly.

[minestarks]

Two things come to mind from reading the user issues:

• Re: DrawRandomInt raise error  #1195 The help text for Qsc.Resolve.NotFound is not that helpful. We know exactly what the problem is, and how the user can fix it (change their profile setting), but the phrasing "help: found a matching item Microsoft.Quantum.Random.DrawRandomInt that is not available for the current compilation configuration" is rather indirect. Since the message is coming directly from the compiler, I understand the desire to keep it generic, but perhaps we can add some additional help text at the VS Code layer?

• Re: Support operations with return type Unit in Resource Estimator #1196 I think part of it is that we currently have no granular steps between Base and Unrestricted. User just wants to be able to return Unit from a program, which is reasonable. Maybe we need a separate Profile defined for Resource Estimation, which allows the Unit return type but still bans other capabilities? (Here I'm using the definition of "Profile" we agreed on a while back - just a friendly alias for a set of runtime capabilities)

[DmitryVasilevsky]

We can place "select profile" as a codelens action on @entrypoint attribute. It could read something like profile: unrestricted and allow selection of profile when clicked on it.