Add field type "Year" #3131
Description
As ad admin user I want to be able to configure a new field type "Year" in order to capture years in the format YYYY, e.g. years of birth.
Objective
This would be helpful for the user in a context where capturing precise dates, e.g. birthdays, would be not allowed/prudent from a data privacy perspective but the user still wants to perform some analysis based on approximated age.
Proposed Solutions & Alternatives
The work-around of asking users to add "fake" dates such January 1st, YYYY, may not be a long-term solution since a) it may confuse users, b) it may not work easily in setups where the birthday/birth-year is retrieved via API from an external source.
Additional context
This need has been expressed by the German University project.