Added 5-arity Scorer.score_refractivity/5 that takes bulk_richardson
alongside best_duct_band_ghz. The existing 1.15× boost now only
applies when Richardson is in the stable regime (< 25) — native-
profile duct cells average 8.7-18.4 for ducting vs 38.3 for
non-ducting, so a duct-band reading under turbulent conditions is
more likely to be torn up by mechanical mixing than to carry a
beyond-LOS signal.
Wiring:
- Weather.nearest_native_duct_info/3 returns {ghz, richardson}; the
bare nearest_native_duct_ghz/3 now delegates.
- PathLive and Propagation.score_with_algorithm/7 both pull the
Richardson value into the conditions map alongside best_duct_band.
- Scorer.composite_score/2 reads conditions[:bulk_richardson] and
passes it into score_refractivity/5.
- Backward compat: 4-arity variant and nil Richardson keep the old
unconditional-boost behaviour so existing callers don't regress.
Graham McIntire
d3b0420457