Add support for protobuf Any type url resolution via ksqldb

[paradigm-shifter]

It would be absolutely amazing if ksqldb could be smart enough to resolve Any types in protobuf schemas via the schema registry so long as the type url points to an already existing schema in the registry.

This would greatly facilitate creating streams within ksql that can change between proto json and avro.

We currently have to use a kafka streams app in order to convert protobufs to json and then let ksqldb take over because of a constraint set on using google.protobuf.Any

[OneCricketeer]

If the feature is for KSQL, perhaps this issue should be relocated? https://github.com/confluentinc/ksql

[ax-mdrinker]

I am having issues attempting to register a Schema that has a nested Any field. Would one of you be able to point me in the right direction for accomplishing that?