* change namespaces for agents and extension methods of the Microsoft.Agents.AI.OpenAI package
* remove unnecessary namespace
* remove unused namespaces
* fix compilation issues and rrolled back removed run methods
* sort usings
* add extension methods for AIAgent to work with OpenAI Responses primitives
* Move OpenAIChatClientAgent and OpenAIResponseClientAgent to samples
* sort usings
* sort usings
* Port store for adding text to a vector store to AF
* Fix typo.
* Change TextSearchStore to sample, and add sample to use it and do rag with a custom schema
* Add more tests and fix broken ones
* Fix merge issue
* Fix sample after merge.
* Convert TextSearchStore to use Dynamic mode to be AOT compatible.
* Add some more clarification on when to use assistant messages in rag searches.