[Epic]: Implement workflows as a primitive in Orleans

[rafikiassumani-msft]

• Work with Azure Durable functions
• Needs design and user studies

We've moved this issue to the Backlog. This means that it is not going to be worked on for the coming release. We review items in the backlog at the end of each milestone/release and depending on the team's priority we may reconsider this issue for the following milestone.