Minor Description
The new IQv2 API was added many release ago. While it is still not feature complete, we should add it to the docs (https://kafka.apache.org/documentation/streams/developer-guide/interactive-queries.html) to make users aware of the new API so they can start to try it out, report issue and provide feedback / feature requests.
We might still state that IQv2 is not yet feature complete, but should change the docs in a way to position is as the "new API", and have code exmples.