This adds a method for creating filters from contact lists. We will be
using this for creating follow timelines.
Signed-off-by: William Casarin <jb55@jb55.com>
This adds local nostrdb thread subscriptions. When navigating to a
thread, we first check to see if we have any active nostrdb
subscriptions for that thread. If not, we create a new subscription. If
we do, we re-use that subscription.
This works by storing thread state in the Threads struct in the Damus
application state.
When we pop a route, we check to see if its a thread route. If it is,
then we try to unsubscribe, but only if that is the last remaining
subscriber for that thread, as there could be more than one.
Signed-off-by: William Casarin <jb55@jb55.com>
This is still single-threaded, so perf is pretty bad. Will need to think
about how to do this more efficiently in a web context where we don't
have threading.
