Add new DiagnosticClient commands for IPC features

[davmason]

Client commands for dotnet/runtime#52175 and dotnet/runtime#52567

[sywhang]

LGTM - would be nice if you can also include a docs change in documentation/diagnostics-client-library-instructions.md since there are some public API additions. The test failures also seem to be coming from runtime that doesn't support the command so... may need to target the tests to versions that support this command after the runtime change gets merged

[davmason]

@mikem8361 @hoyosjs I see failures like this:

System.IO.FileNotFoundException : Dump file does not exist: /__w/1/s/artifacts/tmp/Release/dumps/ProjectK/3.1.15/netcoreapp3.1/SOS.DotnetDumpCommands.Heap.dcd.dmp

I don't see how my changes could cause this. Is this a known issue?

[mikem8361]

The M.D.NETCore.Client's DiagnosticsClient.WriteDump API is failing before the message gets sent to the runtime and it looks like you made a lot of changes to that assembly that affected the WriteDump API.

[davmason]

Ah, I see. Thanks Mike. I will take a look at that

[davmason]

@josalem @hoyosjs can one of you review this? I found the failures - I was encoding a bool wrong in the WriteDump command.

[josalem]

A couple questions, but otherwise this LGTM

[noahfalk]

I think the reversed server is orthogonal, the runtime just needs to be paused at startup? That startup pause can be accomplished regardless whether the port is listening or connecting:

export DOTNET_DiagnosticPorts=foo.sock,connect,suspend
OR
export DOTNET_DiagnosticPorts=foo.sock,listen,suspend