Dynamically generate agent systems in AutoGen

[yeandy]

Why are these changes needed?

Version 1 of the ADAS implementation in AutoGen. Please read the README.md in this PR for details.

Related issue number

This is the PR for the feature initially discussed here https://github.com/microsoft/autogen/issues/4569 and https://github.com/microsoft/autogen/discussions/4486

Checks

• [ ] I've included any doc changes needed for https://microsoft.github.io/autogen/. See https://microsoft.github.io/autogen/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.