What feature would you like to be added?

1. Basic usage
2. Custom termination condition that checks for a special handoff message to the human user to pause the group chat and wait for human user response.
3. Pause and resume of the swarm group chat
4. Reference to the existing core documentation: https://microsoft.github.io/autogen/dev/user-guide/core-user-guide/design-patterns/handoffs.html

Why is this needed?

Useful pattern.