[Feature Request]: Nested chats should be able to run asynchronously

[heyitsaamir]

Is your feature request related to a problem? Please describe.

We currently have a register_nested_chats which you can use to run nested chats. However, if your agents are augmented with async replies (aka using capabilities or subclassing where register_reply takes an async coroutine), then they cannot be run correctly with register_nested_chats because it uses initiate_chats internally instead of a_initiate_chats

Describe the solution you'd like

No response

Additional context

No response