Release v7.3.4

Changed

• The Arc authentication, authorization and identity skill now matches Arc 22.41.1 (it pinned 22.16.0): it documents named and guest authorization policies, fallback baselines, the method-replaces-type rule, Microsoft attribute enforcement, observable-query emission guards, the anonymous discovery and introspection endpoints with the Cratis:Arc:Introspection options, and the trusted forwarded-identity header requirement. It qualifies older behavior by Arc version and names the current defaults tracked in Cratis/Arc#2834, Cratis/Arc#2946 and Cratis/Arc#2939 (#467)