Accurate confirmation messages including target of push operations

[dtrudg]

Is your feature request related to a problem? Please describe. When pushing a key or an image it is often useful to have some feedback indicating you've pushed it to the correct place.

Describe the solution you'd like We have had messages in the past providing push URIs in confirmations, but they have been rolled back as the original code hasn't been well adapted to handle change to the complex mechanism of determining destination services by remote endpoints and/or flags. See e.g. #4

We should aim to return these messages, in a way that they are always correct. This will require considering at which point(s) in the code, from CLI down to implementation of the operations, the URI is known / should be known.

[dtrudg]

Moving to 4.0 will really depend on #78

[dtrudg]

This has become more difficult due to the fact that library push of OCI-SIF is now to a discovered backing registry etc.

We haven't had explicit requests, so postponing for now.