Missing credentialSubject.id property in JWT VC

[italobb]

Bug severity
3

Describe the bug
Although the VC specs for JWT specifies that credentialSubject.id becomes sub, the DIF .well-known DID configuration spec requires an id property in the credentialSubject and it includes that property even in the JWT VCs examples they share. There should be some way to force createVerifiableCredential to keep that field in the credentialSubject.

To Reproduce
Steps to reproduce the behaviour:

1. Use the code below to generate the VC:

const vcArgs: ICreateVerifiableCredentialArgs = {
        credential: {
          '@context': ["https://www.w3.org/2018/credentials/v1", "https://identity.foundation/.well-known/contexts/did-configuration-v0.0.jsonld"],
          type: ["VerifiableCredential", "DomainLinkageCredential"],
          issuer: { id: did },
          issuanceDate: new Date().toISOString(),
          credentialSubject: {
            id: did,
            origin: "acme.com"
          }
        },
        proofFormat: 'jwt'
      };
const vc: VerifiableCredential = await context.agent.createVerifiableCredential(vcArgs);

2. Check the generated JWT VC. It won't have the credentialSubject.id

Observed behaviour
JWT VCs have credentialSubject.id property removed.

Expected behaviour
createVerifiableCredential should keep the credentialSubject.id property maybe by passing some additional parameter in ICreateVerifiableCredentialArgs.

Details
An example JWT VC from identity.foundation: eyJhbGciOiJFZERTQSJ9.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.6ovgQ-T_rmYueviySqXhzMzgqJMAizOGUKAObQr2iikoRNsb8DHfna4rh1puwWqYwgT3QJVpzdO_xZARAYM9Dw

A similar JWT VC, but generated using Veramo: eyJ0eXAiOiJKV1QiLCJhbGciOiJFUzI1NksifQ.eyJ2YyI6eyJjcmVkZW50aWFsU3ViamVjdCI6eyJvcmlnaW4iOiJtZXNoLnh5eiJ9LCJAY29udGV4dCI6WyJodHRwczovL3d3dy53My5vcmcvMjAxOC9jcmVkZW50aWFscy92MSIsImh0dHBzOi8vaWRlbnRpdHkuZm91bmRhdGlvbi8ud2VsbC1rbm93bi9jb250ZXh0cy9kaWQtY29uZmlndXJhdGlvbi12MC4wLmpzb25sZCJdLCJ0eXBlIjpbIlZlcmlmaWFibGVDcmVkZW50aWFsIiwiRG9tYWluTGlua2FnZUNyZWRlbnRpYWwiXX0sInN1YiI6ImRpZDp3ZWI6bWVzaC54eXoiLCJuYmYiOjE2MTQxODQ1NTQsImlzcyI6ImRpZDp3ZWI6bWVzaC54eXoifQ.kch-1I8T2-ciCB5Unv5jjSodDW6PT18_8ufIFNwYPwliUqFvqUA9n1Zykdzuwo-PZRgr8ZG1Yz1MwVDURZjq6Q

Additional context

Versions (please complete the following information):

• Veramo: 1.1.0