ArcKit UK NHS Clinical Safety Overlay

UK NHS Clinical Safety Overlay for ArcKit — 4 commands for NHS DCB0129 (manufacturer) and DCB0160 (deployer) clinical safety case + hazard log, NHS DTAC v3 assessment, and UK MDR 2002 + EU MDR 2017/745 software-as-medical-device classification (SaMD / AIaMD). Adopts Marcus Baw's SAFETY.md spec for DCB0129/0160 file naming and YAML-frontmatter hazard log. Recipe: uk-nhs-clinical-safety. Requires arckit core plugin.