1. convert dataclass types to pydantic basemodel
2. add save_state and load_state for ChatAgent
3. state types for AgentChat
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Co-authored-by: Eric Zhu <ekzhu@users.noreply.github.com>
* AgentChat pause and resume a task
Resolves#3859
* Add
* Update usage
* Update usage
* WIP to address stateful group chat
* Refactor group chat to add reset and flags for running
* documentation