Cleanup csharp project (#137)

* Clean csharp projects

* Fix relative path to README

Prepare source drop of SDKs (#50)

* Prepare source drop of SDKs

* Get the latest CS SDK update

* Fix link

* Remove empty test

* Pick up foundry-chat project at 822bd658

* Move samples around

* Move the sample back next to the SDK for now

* Make cloud vs. local a bit more configurable.  Just a start.

Include launch.json for debugging

remove keys

* fixup dynamic model selector and do general code cleanup

---------

Co-authored-by: Cory Hendrixson <[email protected]>