WIP [NX-416] Expose optimistic versioning to Capabilities

This has a bunch of problems... but this is as far as I've gotten ATM.

Specifically, this won't work as the usage of CapabilityIdentity is not expect to change, and its not update on a change to reflect.  The UI uses this as part of URL and if it did update to reflect version it would have to update the bookmark too.

Unsure if hiding version inside of CapabilityIdentity is proper, though the alternative is to expose API changes to pass this around which I'm also unsure of.