silent; code_execution_config; exit; version

[sonichi]

Why are these changes needed?

1. Support silent mode to hide unnecessary messages in chess and group chat. (experimental)
2. Support lookback for multiple messages in code_execution_config. (experimental) @LittleLittleCloud
3. Improve group chat speaker selection. @LittleLittleCloud
4. Support exit group chat when human input is "exit".
5. Bump version to 2.0.0.

Related issue number

Checks

• I've included any doc changes needed for https://microsoft.github.io/FLAML/. See https://microsoft.github.io/FLAML/docs/Contribute#documentation to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

[sonichi]

Did you compile and check if the doc pages on the website are good? If so, LGTM.

Partially. I made more changes when I checked. But it'll be good to have a second eye on it.

[thinkall]

I've fixed errors in retrieve chat. One more thing is that there is a function _generate_math_reply in math_user_proxy_agent.py, but I don't see it being called when running autogen_agentchat_MathChat.ipynb. If it will be called, looks like it should be updated to handle parameter config.

[sonichi]

I've fixed errors in retrieve chat. One more thing is that there is a function _generate_math_reply in math_user_proxy_agent.py, but I don't see it being called when running autogen_agentchat_MathChat.ipynb. If it will be called, looks like it should be updated to handle parameter config.

Thanks. I fixed that.