.NET: Adding Semantic Kernel - Migration Samples (#499)
* Guidance
* Guidance
* WIP Migration Preps
* Move to single file projects
* Update guidance code and final adjustments to ensure all feature compatibility
* Move from demos to samples
* Address format
* Address chat client pipeline order
* Update project naming
* Revisition on README
* Remove unused ctor
* Address feedback
* Address feedback
* Address merge conflict fix
* Address SK versioning
* Address folder naming
* Address feedback