EVO-69: add createdAt to 15 static catalog tables + fix lookupOptions.createdAt NOT NULL

Fleet EVO-69 child. (1) ALTER 15 static catalog/lookup tables (antecedentesCatalog, cirugiaAttributeKeys, cirugiaAttributeOptions, cirugias, cirugiasCategorias, cirugiasSubcategorias, complicaciones, dias, modulos, piezasDentarias, regionesAnatomicas, rateLimitHits, rolesEnPractica, sedes, tratamientos) ADD createdAt timestamptz NOT NULL DEFAULT now(). (2) Backfill lookupOptions.createdAt nulls then SET NOT NULL. Additive DDL, audit pre-apply review, update db/schema.md.