* Integrate Microsoft.Extensions.AI as a foundational building block
As with logging abstractions coming from M.E.Logging and DI abstractions coming from M.E.DependencyInjection, M.E.AI provides the relevant AI abstractions.
- Adds AsAIFunction and GetAIFunctionsAsync methods for getting functions for tools via a client.
- Uses AIFunctionFactory to implement McpServerBuilderExtensions.WithTools.
- Adds a RequestSamplingAsync overload that accepts ChatMessages/Options.
- Adds an AsSamplingChatClient method that provides an IChatClient usable on the server to request sampling of the client.
- Adds a CreateSamplingHandler method to enable an IChatClient to be easily used to satisfy sampling requests on the client.
- Deprecate McpDotNet.Extensions.AI.
* Address PR feedback
