rw-core utilities and engineering-unit review

The local rw-twincat-core repo is a useful design reference, but its utility folder includes process-plant and project-specific code. TcForge targets discrete assembly machines. This review selects behavior for a real TcForge consumer rather than importing an entire category. No utility implementation was copied.

Reference area	Decision	Reason
Task cycle time, first-order low-pass filter, IO quality	Already covered in TcForge	F_GetTaskCycleTime, FB_LPF_FirstOrder_IIR, and FB_IOQualityMonitor have explicit task, finite-value, freshness and recovery behavior.
FB_CycleGuard	Do not import	Skipping a second call silently could hide a double-owner wiring error. Its test-build bypass also means tests do not exercise the same behavior. TcForge requires one cyclic owner and detects execution gaps.
Bitmask functions and FB_Select	Defer	FB_BitMatrix64 serves current bit-state users. The selector assumes matching array bounds and needs a defined no-match and mismatch policy before becoming a common API.
Moving average, ramp/setpoint limiters, PWM, stopwatch	Defer	These can help specific sensors or drives, but need a real consumer and explicit startup, invalid-sample, task-timing and safe-output semantics. The reference stopwatch measures system time; sequence timing should use the PLC task/timer contract.
CoE SDO, Modbus TCP, module registries, response generators and mock VFD	Keep out of the core for now	They bind to specific buses, hardware, application composition or simulations. Add an optional adapter or test model when a machine needs one.

E_Unit lives with analog IO, not in the utility folder. The earlier TcForge version inherited a process-heavy catalog (pH, turbidity, conductivity, liquid and gas flows) and defaulted every analog channel to PERCENT. We have no external consumers yet, so the enum now uses explicit codes for common discrete machine measurements: position, angle, speed, force, torque, mass, pneumatic pressure, temperature, electrical values, count and time. Unconfigured channels publish UNSPECIFIED. The assembly example explicitly labels its pressure and height sensors. The enum is HMI metadata, not a unit-conversion system.