Missing Migrants on a Map (Multiple Views w/ Brushing)
This example visualizes missing and deceased migrants on a world map, with a linked time-series bar chart below. Brushing the histogram filters the map’s circles by date range, while hovering any circle reveals its location, date, and total count. The map uses `d3.geoNaturalEarth1` and `d3.geoPath` for the sphere, graticules, and country outlines, with circle radii scaled by `d3.scaleSqrt`. The histogram aggregates data monthly via `d3.histogram` and `timeMonths`, with brushing implemented through `d3.brushX`. Data comes from a CSV of global migrant incidents, rendered in SVG.