Score time-of-day per grid point using longitude/15 solar offset instead of hardcoded CST/CDT. Add PWAT as 10th scoring factor. Refine pressure thresholds. Update ML model and training pipeline to use local solar time.
13-feature feed-forward network (atmospheric + temporal + frequency). Includes build, init, predict, encode_features, save/load to disk. Model weights saved to priv/models/propagation_v1.nx (gitignored). Not yet trained — scaffolding only.
