server: time/detect blocked message delivery actions (#546)

* server: log slow operations

* v3.3.1

* base-64 encode IDs

* fixing test

* log

* log

* revert

* log

* fix

* reduce timeout

Co-authored-by: JRoberts <8711996+jr-simplex@users.noreply.github.com>

src/Simplex/Messaging/Notifications/Server.hs

@@ -205,7 +205,6 @@ ntfSubscriber NtfSubscriber {smpSubscribers, newSubQ, smpAgent = ca@SMPClientAge
           incNtfStat ntfReceived
         SMP.END -> updateSubStatus smpQueue NSEnd
         _ -> pure ()
-      pure ()
 
     receiveAgent =
       forever $