forked from 1b-agent/opencadstudio-upstream
USERI/USERR set one of five integer/real header registers and needed both inputs (register + value) typed on one line; bare printed usage. Add a two-step front-end (UserRegCommand): it prompts for the register as 1–5 buttons, then the value, and dispatches USERI/USERR <n> <value> to the existing inline handler. The argument arm now requires a space so the bare name reaches the stepped command.