[WACI-ISSUANCE] missing pieces

[sudeshrshetty]

• adapter should persist subset of offer credential data (by thread, connectionID or txnID) to be used later in request credential step to avoid calling issuer services again for preparing credential fulfillment
• wallet user declining should send problem report to adapter which should delete in any fulfillment data persisted for given thread
• strategy on reusing txnIDs, connections, invitation IDs - need grooming
• Figure out the way to pass the matched credentials result back to the issuer #635 list of allowed DIDs should be configurable #637 Changes to Adapter Issue API URL #632