ios, core: better notifications processing to avoid contention for database (#3485)

* core: forward notifications about message processing (for iOS notifications)

* simplexmq

* the option to keep database key, to allow re-opening the database

* export new init with keepKey and reopen DB api

* stop remote ctrl when suspending chat

* ios: close/re-open db on suspend/activate

* allow activating chat without restoring (for NSE)

* update NSE to suspend/activate (does not work)

* simplexmq

* suspend chat and close database when last notification in the process is processed

* stop reading notifications on message markers

* replace async stream with cancellable concurrent queue

* better synchronization of app and NSE

* remove outside of task

* remove unused var

* whitespace

* more debug logging, handle cancelled read after dequeue

* comments

* more comments

src/Simplex/Chat/View.hs

@@ -279,6 +279,7 @@ responseToView hu@(currentRH, user_) ChatConfig {logLevel, showReactions, showRe
   CRNtfTokenStatus status -> ["device token status: " <> plain (smpEncode status)]
   CRNtfToken _ status mode -> ["device token status: " <> plain (smpEncode status) <> ", notifications mode: " <> plain (strEncode mode)]
   CRNtfMessages {} -> []
+  CRNtfMessage {} -> []
   CRCurrentRemoteHost rhi_ ->
     [ maybe
         "Using local profile"