osx: try badging icon for unread

osx/kordophone2/ConversationListView.swift

@@ -101,6 +101,11 @@ struct ConversationListView: View
                     .map { Display.Conversation(from: $0) }
                 
                 self.conversations = clientConversations
+
+                let unreadConversations = clientConversations.filter(\.isUnread)
+                await MainActor.run {
+                    NSApplication.shared.dockTile.badgeLabel = unreadConversations.isEmpty ? nil : "\(unreadConversations.count)"
+                }
             } catch {
                 print("Error reloading conversations: \(error)")
             }

osx/kordophone2/Models.swift

@@ -26,7 +26,11 @@ enum Display
         var isGroupChat: Bool {
             participants.count > 1
         }
-        
+
+        var isUnread: Bool {
+            unreadCount > 0
+        }
+
         init(from c: Serialized.Conversation) {
             self.id = c.guid
             self.name = c.displayName