Make the unread message count 4 digits instead of 2

Session/Conversations/ConversationVC.swift

@@ -494,8 +494,8 @@ final class ConversationVC : BaseVC, ConversationViewModelDelegate, OWSConversat
             unreadViewItems.remove(at: index)
         }
         let unreadCount = unreadViewItems.count
-        unreadCountLabel.text = unreadCount < 100 ? "\(unreadCount)" : "99+"
-        let fontSize = (unreadCount < 100) ? Values.verySmallFontSize : 8
+        unreadCountLabel.text = unreadCount < 10000 ? "\(unreadCount)" : "9999+"
+        let fontSize = (unreadCount < 10000) ? Values.verySmallFontSize : 8
         unreadCountLabel.font = .boldSystemFont(ofSize: fontSize)
         unreadCountView.isHidden = (unreadCount == 0)
     }

Session/Shared/ConversationCell.swift

@@ -210,8 +210,8 @@ final class ConversationCell : UITableViewCell {
         isPinnedIcon.isHidden = !threadViewModel.isPinned
         unreadCountView.isHidden = !threadViewModel.hasUnreadMessages
         let unreadCount = threadViewModel.unreadCount
-        unreadCountLabel.text = unreadCount < 100 ? "\(unreadCount)" : "99+"
-        let fontSize = (unreadCount < 100) ? Values.verySmallFontSize : 8
+        unreadCountLabel.text = unreadCount < 10000 ? "\(unreadCount)" : "9999+"
+        let fontSize = (unreadCount < 10000) ? Values.verySmallFontSize : 8
         unreadCountLabel.font = .boldSystemFont(ofSize: fontSize)
         hasMentionView.isHidden = !(threadViewModel.hasUnreadMentions && thread.isGroupThread())
         profilePictureView.update(for: thread)