Allow parameter and return types of route handler delegates (API Controllers) to contribute to endpoint metadata

[brunolins16]

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Is your feature request related to a problem? Please describe the problem.

Introduce the capability for types used for parameters and return values for API controller actions to contribute to metadata of the endpoint they're mapped to. This will allow types that implement custom binding logic via TryParse and IResult types, to add metadata that describes the API parameters and responses in Swagger UI and OpenAPI documents.

This is an idea of feature parity with Minimal API, after #40646.

Describe the solution you'd like

We should introduce the same support for the new interfaces, IEndpointParameterMetadataProvider and IEndpointMetadataProvider that currently is implemented in Minimal Actions.

Additional context

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We're moving this issue to the .NET 7 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
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[captainsafia]

Triage: Bruno proposes implementing this as an ApiConvention.

We also discussed whether this would worthwhile to do if MVC does not support BindAsync and concluded there is value in this work even though MVC doesn't support BindAsync as of writing.