Pure-Python port of the Input Sheet RGB→PWM pipeline (color management
+ luminance management + temperature compensation) used by the ALM
firmware. Exposes compute_pwm(r, g, b, temp_c) returning both the
non-compensated and the temperature-compensated 16-bit PWM tuples.
Imported by tests/hardware/alm_helpers.py to predict expected PWM
values from RGB inputs in PWM-validation assertions.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
