Failure and Error Signaling

[Zetanova]

Here are some small ideas for improvements in the topic Failure and Error Signaling

1. the current Status.Failure message has only an exception as payload,
   it could be extended with a "command" property to indicate the source.
   The receiver of the Status.Failure message could handle the error and resend
   the command back for an retry.

2. Task.Exception always returns an AggrateException and the PipeTo extensions could unwrap it with:

if(ex is AggregateException ae && ae.InnterExceptions.Count == 1)
     ex = ae.InnerException;

This would help the receiver to handle the error better.
But it maybe an unexpected change for some users.

3. There is still no serializable Error payload message.
   Exceptions are not great for serialization / wire.

[Zetanova]

1. resolved with Improve status messages #5226

2. half resolved with Pipe of Canceled Tasks #5123
   The problem is that maybe some users expecting AggrateException in the Status.Failure message.
   @Aaronontheweb How can give the ok for such change?

3. I will make a proposal not only for exceptions,
   it is needed in some scenarios to relay serialized messages
   or to have the option to deserialize them later
   or handle them after deserialization failure TryGet pattern

[Zetanova]

3. Feature: Payload Message #5231