This commit adds non-archived group messages and `group_message_summary` notifications in the messages tab in the user menu. With this change, the messages tab in the user menu now includes 3 types of items:
1. Unread `private_message` notifications (notifications when you receive a reply in a PM)
2. Unread and read `group_message_summary` notifications (notifications when there's a new message in a group inbox that you track)
3. Non-archived personal and group messages
Unread `private_message` notifications are always shown first, followed by unread `group_message_summary` notifications, and then everything else (messages and read `group_message_summary` notifications) sorted by recency (most recent first).
Internal topic: t/72976.
5a5625460b