Add ZWrapperBase so that setMetadata* functions can handle ZWrappers in addition to bare Z22s.
also:
- add
isZEnvelope
function (will be useful for coming orchestrator changes); - move the
setMetadataValues
function here (will be removed from the orchestrator); - call
asJSON
on the arguments during error creation (necessary compromise to deal withZ99
s in errors now)
Bug: T351473