Test case 04: Enforce validations in the presentation flow

[pcosio]

I was executing the Test Case 04 that is related to RFC002 and I discover a possible issue that maybe could be fixed in order to enforce and ensure that the presentation flow is done correctly.
I've realized that the iGrant wallet at the time of performing the presentation, it sends the following presentation_submission:

{
   "definition_id": "d49ee616-0e8d-4698-aff5-2a8a2362652d",
   "descriptor_map": [
       {
           "format": "vc+sd-jwt",
           "id": "abd4acb1-1dcb-41ad-8596-ceb1401a69c7",
           "path": "$",
           "path_nested": {
               "format": "jwt_vc",
               "id": "abd4acb1-1dcb-41ad-8596-ceb1401a69c7",
               "path": "$.vp.verifiableCredential[0]"
           }
       }
   ],
   "id": "8D3529B7-5218-424E-AB31-643032F11102"
 }

There is an issue with the value ""jwt_vc" that is inside the format field within the path_nested object.
That value does not satisfy the presentation definition (https://dss.aegean.gr/rfc-issuer/presentation-definition/itbsdjwt) because it should be "vc+sd-jwt". Moreover, the Verifier could not parse/decode the credential because it is expecting a jwt_vc (defined in the presentation submission) and it is a sd-jwt vc.

My proposal is that the Aegean Verifier could include these validations about the Test Case 04. It means:

• extract the credentials from the vp_token following the presentation_submisssion
• decode the credentials and validates that it's complying with the format and constraints defined in the presentation definition. In the context of test case, it means to exist the fields given_name, last_name and vct field to be VerifiablePortableDocumentA1SDJWT.

If not, it could lead to have issues with the wallets and not to ensure the interoperability between the different wallets and verifiers involved in the project