Improve EUDIW interop
Created by: nodh
Updates the implementation of OIDC SIOPv2 and OpenID for Verifiable Presentations, refactors interfaces of public classes to further improve the interoperability with EUDIW reference implementation.
These changes should allow Wallet implementations to generate a correct response to EUDIW verifier at https://verifier.eudiw.dev/home
Fixes #47 (closed)