Same-name stops within 50m (opposite sides of a road, different platforms/entrances) are now merged into one marker at the cluster centroid. Uses scipy hierarchical clustering (single linkage, distance criterion). Stop counts after clustering: bus: 1610 -> 892 markers metro: 91 -> 46 markers s_tog: 76 -> 34 markers regional: 27 -> 10 markers Threshold configurable via styling.yaml stations.stop_cluster_m.