replace client_metadata_uri with client_metadata parameter in OpenID4VP flow

[gerardsn]

The next version of the OpenDI4VP spec deprecates the client_metadata_uri in favor of directly adding the client_metadata to the authorization request.

We should probably also replace the presentation_definition_uri with presentation_definition. This way a wallet only needs to make 1 API call to collect the request object (JAR) that contains all relevant info for the request