16975 grouped attributes on overview tab

[``* `#16975` Grouped attributes on overview tab``](https://community.openproject.org/work_packages/16975)

Furthermore, this PR implements:
- https://community.openproject.org/work_packages/16976
- https://community.openproject.org/work_packages/16977
- https://community.openproject.org/work_packages/16979
- https://community.openproject.org/work_packages/16978
The styleguide should be updated along with this change.