[WIP] Kaf notifications

| Q                    | A
| -------------------- | ---
| Bug fix?             | N
| New feature?         | Y
| BC breaks?           |
| CI currently passes? |
| Tests pass?          | Y
| Scenarios pass?      |
| Checkstyle issues?*  | 
| PMD issues?**        | 
| Changelog updated?   |
| Fixed tickets        |
| Doc PR               |
Because we allow users to mark all as viewed -> don't need ids for that