[VCDM] Refactor the cloud-agent REST API to be agnostic to the VC type

### Proposed feature

In the current implementation, the [createCredentialOfferEndpoint](#) and the [CreateIssueCredentialRecordRequest](#) are used for all VC types: JWT, AnonCreds, SD-JWT.
The request contains the fields belonging to the DIDCommV2 Issue Credential protocol and a set of fields required to issue any credential type.

The problem with this solution, that additional validation logic should be used in the cloud-agent to check the consistency of the params and the HTTP clients should carefully compose the request. The request contains the fields belonging to the DIDCommV2 Issue Credential protocol and a set of fields required to issue any credential type.

### Feature description

The idea is to refactor this endpoint to be agnostic to the VC types (as DIDComm protocol is) and keep only the fields that control the Issue Credential protocol:
- goal
- goalCode
- connectionId
- automaticIssuance

All other fields that belong to the particular VC type should be deprecated and removed.

The VC that will be issued should be created using dedicated endpoints (one per VC type and VCDM) and referenced in the request using reference.

### Anything else?

_No response_