In Part 1, we built the framework: 375 H3 Res 10 cells across a 562-hectare Iowa corn field, Moran's I = 0.807, confirming strong spatial structure, and 12 K-Means management zones that cut within-zone soil-nitrogen CV by 66.8%. The zones are built. The cells are assigned. Each row in our DataFrame represents a ~1.5-hectare prescription unit with aggregated soil N, organic matter, pest counts, and mean yield. Now let's open the hood and look at what those zones actually contain, because the nu...