I bet we could make the SubEndpoint a scoped object which automatically unsubscribes when it is dropped ...

I'm missing the outer flow on outbox ... is this right?:

1. user clicks to view thread
2. we one-time fetch k:10002 for author and determine authors relays
3. we subscribe to the thread with SubConstraint::OutboxRelays(author_relays)
4. SubMgr evaluates relays, possibly changes current set
5. user disposes of thread view, we remove subscription (and reevaluate relays)

OutboxRelays means "make sure we have at least one of these in our active set"

It might be useful to have a SubConstraint::Local which only queries local and doesn't alter remote subscriptions

liking the sounds of this so far!

• I force pushed the first commit, cleaning up the compiler comments etc
• the second commit makes the SubReceiver (was SubEndpoint) scoped and unsubscribes when it goes out scope.

Is the second commit a good thing? I used an Arc<Mutex> to calm rust re: the SubMgr reference issues ...

Renamed to subman

rebased on master