Mirrors ifcopenshell.util.geolocation: HelmertTransformation parameters
(IfcMapConversion / IfcMapConversionScaled / IfcRigidOperation, plus
IFC2X3 ePSet_MapConversion), get_wcs from IfcGeometricRepresentationContext,
local2global, and auto_local2global. Lives in src/ifcviewer/ for now;
will move out when ifcopenshell.util is ported to C++.
Not yet wired into the streamer. A subsequent commit fixes the
unit handling for the iterator's meter-by-default output.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Dion Moult