DRAFT: AIPlugin, SKFunctionResult and InputWithType attributes

[shawncal]

Description

Filling out the attributes required to fully describe a skill and its functions for 2 applications:

• Publishing SK Skills AI (ChatGPT) Plugins -- REST microservices, documented with OpenAPI Specs
• Describing function inputs and results, often comprising complex json object return types, coming from REST functions, GRPC functions, and AI plugins registered to the kernel.

DRAFT: Open for comments. Naming? Preferences between a large attribute with many required properties, vs many small attributes (that are all still "required")?

Input and Result attribute type modeled after OpenApiResponseWithBodyAttribute and its parent class OpenApiPayloadAttribute.

Contribution Checklist

• [ ] The code builds clean without any errors or warnings
• [ ] The PR follows SK Contribution Guidelines (https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
• [ ] The code follows the .NET coding conventions (https://learn.microsoft.com/dotnet/csharp/fundamentals/coding-style/coding-conventions) verified with dotnet format
• [ ] All unit tests pass, and I have added new tests where possible
• [ ] I didn't break anyone :smile:

[shawncal]

@dluc @SergeyMenshykh this is the code associated with dev doc shared last week. I'm not committed to any naming or even the number of attributes -- only that the properties exposed therein are required for both publishing and using AI Plugins and other OpenAPI-derived functions. One option, if we don't want the AI Plugins attributes in the core kernel, would be to package them in another extension package. Can you please take a look, and let me know what you think?

[shawncal]

no feedback. Closing PR. Reassigning to Engineering for a final design, implementation and PR.