Outline a mechanism for polling the status of sub objects like `invitations`

**Is your feature request related to a problem? Please describe.**
This issue is related more from a need that I have recently had. While implementing custom workflows for issuing credentials either:
- when the customer is using say single sign on and does not see the invitation emails
- invitation emails are sent to the user but the completely ignore accepting an invitation for a mobile credential

in both instances the mobile credential is consumed on the server but isn't actually in use by a user.

In many of these instances you would want the middleware system to be notified of the status of these objects. At the moment I am scheduling tasks that allow me to poll a status of these objects and deploy application specific solutions.

**Describe the solution you'd like**
The proposal here is to outline a formal way that the library allows us to track these items and call back and update the application layer.

I am aware that this might mean that the library has dependencies on something like `celery` which you wouldn't want to impose as there are other libraries like `taskiq` that are also in wide use.

The solution could end up being some recipes that we make available as part of the documentation?

**Describe alternatives you've considered**
As mentioned in the initial description that I have an application level solution that uses `celery` based queues.

**Additional context**
This may be way too application specific for us to come up with a generic solution. This ticket is for us to explore the idea.