Add Output Descriptors to create Credential Manifest flow

[kirahsapong]

Need to add output descriptors to define metadata in the stored Credential Manifest to prescribe how the Credential will rendered to the Issuer in the Credential Manifest Details page. Currently it is rendered according to the site theme configurations.

Also should address adding a way to include more complex Output Descriptors so that a single Credential Manifest can produce multiple Credentials for an approved application.