* Adding draft version of workflows design doc.
* Adding message flow diagrams and fixing group chat sample.
* Added sequence diagram for fan_in with WhenAny
* Updating workflows design
* clean up
* Clean up request & response contents
* Add more future enhacements
* message_handler -> handler
* remove mention of visual designer
* Minor updates and rename
* Name reformat
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Co-authored-by: Chris <66376200+crickman@users.noreply.github.com>
Co-authored-by: Tao Chen <taochen@microsoft.com>
Co-authored-by: Eric Zhu <ekzhu@users.noreply.github.com>
Ben Thomas