Build spec and host brief carried in from C:\Claude and WRPS/02-env; the
plant model (equipment, tags, alarm bitmask, enums, unit conversions) is
derived from WRPS/04-plc/register-map.csv, WRPS/05-scada/modbus/scada-points.csv
and WRPS-CTL-003.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
