ios: channels and chat relays ui (#6634)

src/Simplex/Chat.hs

@@ -37,6 +37,7 @@ import Simplex.Chat.Protocol
 import Simplex.Chat.Store
 import Simplex.Chat.Store.Profiles
 import Simplex.Chat.Types
+import Simplex.Chat.Types.Shared (GroupMemberRole (..))
 import Simplex.Chat.Util (shuffle)
 import Simplex.FileTransfer.Client.Presets (defaultXFTPServers)
 import Simplex.Messaging.Agent
@@ -113,6 +114,7 @@ defaultChatConfig =
       highlyAvailable = False,
       deliveryWorkerDelay = 0,
       deliveryBucketSize = 10000,
+      channelSubscriberRole = GRObserver,
       deviceNameForRemote = "",
       remoteCompression = True,
       chatHooks = defaultChatHooks