Revamp notifications

Is your feature request related to a problem? Please describe.
Sorry, I'm bringing up this point again, which was already included in the previous process step. Improvements to the notification system would be very helpful for us. We've had cases of unwanted notifications with strange content.

Describe the solution you'd like
Notifications are central to engagement, both for participants who want to stay connected and for administrators who need timely updates. We should rethink their format, content, and delivery. A systematic review of notifications will help ensure they are more useful, less intrusive, and better adapted to the diverse needs of the community.

Describe alternatives you've considered
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Additional context
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Does this issue could impact on users private data?
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