Group/collect notifications of the same type to only show them once

When a client has sync conflicts, it will show 1 notification per conflict. If there are 100s, this is not use full for the user.

### High Level Concept Idea

- Issue entry in the activity log
- Delay notification by x seconds
- Collect notification
- If next notification is of the same type, count++ and restart the delay
- If no notifications of the same type come up during the delay, trigger notification with the count like "25 Sync conflicts"