// sankeyUtils.ts export function sankeyTooltip(echartNodes: any[], nodeValues: number[]) { return (params: any) => { if ('source' in params.data && 'target' in params.data) { const sourceName = echartNodes[params.data.source].name; const targetName = echartNodes[params.data.target].name; const sourceValue = nodeValues[params.data.source]; return `