Clarify Entity Authorizations in OpenAPI spec.

[andorsk]

Additional language around https://github.com/trustoverip/tswg-trust-registry-protocol/blob/main/api/toip-tswg-trustregistryprotocol-v2.yaml#L74C1-L75C1 and https://github.com/trustoverip/tswg-trust-registry-protocol/blob/main/api/toip-tswg-trustregistryprotocol-v2.yaml#L113 would be appreciated to delineate the differences between the two. They both return AuthorizationResponseListType and the summaries are the same: Determine whether an Entity has a particular Authorization. It is unclear what the purpose of the two endpoints are vs. having a single endpoint.

[andorsk]

Thoughts here that were discovered over IIW: To prevent collisions, I'm leaning toward the authorizations data model MUST be referenced by an globally unique identifier. A DID is sufficient for this, but probably any globally unique identifier is sufficient.

The uniqueness attribute is required to prevent authorization namespacing collisions.