This PR addresses an issue where mention_notification was being
overwritten by assigned_conversation_new_message notifications.
Similarly, participating_conversation_new_message was taking priority
over assigned_conversation_new_message.
The fix ensures that additional notifications are not created in these
scenarios by establishing a priority order for notifications as follows:
1. mention_notification
2. assigned_conversation_new_message
3. participating_conversation_new_message
This change maintains consistency and prevents redundant notifications.
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Note: In the older implementation of notifications in Chatwoot,
notification objects were created only if the user had subscribed to a
specific notification type. With the new inbox_view model, we are
changing this approach to create notification objects in all cases. This
PR updates the services to remove reliance on notification preferences,
simplifying the logic.
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Caveat: Since we don’t create extra notifications for new messages if a
mention_notification already exists, a user subscribed to
new_message_notification push/email notifications but not to
mention_notification will not receive notifications in these cases.
