Add Demo Data user + developer wiki pages - Demo-Data: what it seeds (incl. the RBAC example), what import does, tips. - Demo-Data-Developer-Guide: the tier/@ref/token model, string->id lookups, transaction/repeatability guarantees, and a step-by-step for adding demo data to a new module. Colour-keyed file table; links the D001 diagnostic. - Sidebar entries under System.