a7ff882e21
Role badges rendered gray for everything except admin, with no way to tell roles apart. Add an optional color per role, matching how statuses and types carry one: new roles.color column (migration 7d27_roles_color), color threaded through the role API and the user serializer, and a ColorSwatchPicker in the role editor. Badges use the role's color with contrast-aware text and fall back to the old admin/gray classes when unset.