Both TODO.md backlogs and the README's architecture section still
described the Kalman-filter/heat-diffusion design that's since been
replaced by the delay-line Pot model and Kalman-free Smith predictor.
Check off the items that rewrite already fixed (heat-loss units,
transport delay vs. single-pole lag, three-Kalman-tuning), note how
the kn/sensor-noise item was resolved differently than proposed, and
add newly-spotted issues: brewpi.py wiring set_model_power
unconditionally (breaks pid_type "Normal"), kalman.py being dead code
in production, stale Kalman/kn keys in the config templates, and
debug print()s left in Pot.process().
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>