Notification API tag grouping for duplicate alert suppression

The goal is to use the Notification API tag option to group related user alerts and suppress duplicate popups while keeping important updates visible.

The design must balance permission timing against user annoyance, decide when requireInteraction is appropriate for persistent alerts, and account for differing browser implementations of tag replacement and interaction requirements.

There is uncertainty about how tag-based replacement interacts with requireInteraction across browsers, and whether grouping behavior is consistent enough to rely on for noise reduction.

Does tag replacement produce a single visible notification on Safari iOS as it does in Chrome and Firefox? How does requireInteraction affect the lifecycle of a tagged notification when the user dismisses it? What permission state considerations should guide when to request Notification permission?