b3b8b92520
The instant_rate mode existed in the enum but had no normalizer, so normalizing a power/flow sensor threw NotSupportedException. InstantRateNormalizer integrates the rate over time (trapezoidal, attributed to each interval's end reading); a per-hour rate in the meter's unit yields the consumption unit (kW->kWh, L/h->L). Registered in the engine; meter editor shows a mode hint. +4 Core tests. Claude-Session: https://claude.ai/code/session_01Kib2MniVFbD95fkgLgBBnB