[core] /.well-known/core and multicast addresses

[Jim Schaad <[e-mail]>]

I am unsure how to get to the correct answer in this case.

I do a multicast get to /.well-known/core
The response comes back on a unicast address with relative URIs and without
an anchor.
I resolve the relative URI against ???

At this point I am supposed to resolve against the origin of the target URI,
but from my understanding this would be the multicast address which is
probably the wrong answer but may not be.  It would depend if this is a
really a multicast resource or is just a unicast resource.  However I am not
sure where the hint is going to be deep in my code that I should resolve
against the return address rather than against the query address.  I would
know that using the return address is wrong in the event that the query went
first to a proxy or gateway before going to the correct location.

Jim