We'll need an endpoint which will take an identity/org and return the default workspace for that org. This will be needed by inventory. Initially we can assume to use the x-rh-identity and the org_id value from that, effectively just using the authenticated user's identity/tenant/org knowing that in the future we may need to support a different form of authentication/token.

Proposed: /workspaces/?type=all|default|root|ungrouped where "all" would be the default if the param is not supplied. Alternately we could have a separate endpoint, but it would make more sense to do this if we only ever needed default, for something like /workspaces/default/