[CWEP002] Add support for computed attribute synchronization
Related to #3546717.
Test and handle the behaviour with several formulas and identified use cases. To
do so add a birth year and a computed attribute age to Person in the test
schema.
Add some entities
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As manager, you can access to entity creation forms by using the `site management`_ page.
.. _`site management`: manage
As regular user, the index page or the action box may propose some links to create entities according to the context.