* Handle external input request and response conversion for workflow as agent scenario
* Remove unnecessary test comment
* Fix PR comments
* Updated to fix edge cases, and add more tests.
* Update pending requests to use typed properties instead of relying on StateBag. replying to PR feedback.
* Fixed external response de-dup and updated possible brittle test.
* Address PR comments on sending turn token for normal messages and handle contentId collision by source agent
* Remove unnecessary serialization element and address pr comment on intercepted outgoing requests
* Updated MEAI changes for UserInput request and response abstractions.