Schema for attribute groups — reusable, translatable sets of product characteristics ("Idea doors": Color, Trim, Surface…).
Groups are global (cross-catalogue). name holds the primary-language
display text; other languages live in data per the module's multilang
convention. status "archived" is not deletion: an archived group
stays readable on items that hold it but leaves the assignment picker.
A group referenced by any item cannot be hard-deleted (RESTRICT FK from
the assignment table); unreferenced groups delete via the context's
explicit transactional cascade.