Roll-Cage Tube Mass, Center-of-Gravity Shift & FIA Wall-Thickness Checker

Deterministic 3D tubular truss linear mass-moment integration + FIA Appendix J Art. 253.8 tensile/bending modulus & minimum wall-thickness geometry check engine (.json, .csv, .dxf) built for Custom Cages UK, Safety Devices, FIA Motorsport, Wiechers — zero-upload ephemeral Wasm RAM execution.