Provide support for "claims" parameter within authorize request

[dur8wz]

We'd like to request the addition of support for the claims parameter within authorize requests, as defined by the OpenID Connect Core 1.0 specification, section 5.5, "Claims Parameter" (https://openid.net/specs/openid-connect-core-1_0.html#ClaimsParameter).

This parameter allows clients to request specific sets of claims to be returned in the ID Token or UserInfo endpoint, and importantly, can specify "essential" claims.

[wcabus]

Our team has been investigating supporting the OpenID Connect claims parameter, but adding support for this is not trivial as it involves changing various parts of IdentityServer.

Could you share more information, i.e. use cases, as to why you'd like this feature to be implemented?