route namespace

design notes for #850

I estimate completing the implementation will take half a day.


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UPDATE (from Adam): This took over a day to change it from design to implementation, including hours of pairing, but the estimate was for Jean-Paul alone and I'm slower. There are also a few TODOs with questions about how to continue.

Fixes #850 

As mentioned above, this is either unnecessary or the interface should be expanded... and it's not clear to me what adding it to the interface buys (but feel free to argue for adding it if you think it's a good idea).