Adds heating_min_ambient_c (default 15°C) to season config. When outdoor
temperature is at or above this threshold, SG-Ready is suppressed even if
the calendar month is within the heating season. Prevents unnecessary heat
pump boost activation on warm spring/autumn days.
Logic: heating active = in_heating_month AND ambient < threshold
Zero value (unset) disables the temperature gate (calendar-only, old behaviour).
New test: TestHeatingPeriodAmbientSuppression covers warm-day suppression,
cold-day pass-through, and summer month independence.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Lutz Finsterle
0b51ce5240