fix(ui): отличать пустую историю трафика от нулевой

components/reui-kit/traffic-rx-tx-chart.tsx

@@ -60,8 +60,8 @@ function toChartData(rx: number[], tx: number[], rangeMinutes: number) {
     const minutesAgo = Math.round((1 - i / denom) * rangeMinutes)
     return {
       time: formatRangeAgo(minutesAgo),
-      rx: rx[i] ?? 0,
-      tx: tx[i] ?? 0,
+      rx: Number.isFinite(rx[i]) && rx[i] >= 0 ? rx[i] : null,
+      tx: Number.isFinite(tx[i]) && tx[i] >= 0 ? tx[i] : null,
     }
   })
 }
@@ -82,8 +82,11 @@ export function TrafficRxTxChart({
   const data = toChartData(rx, tx, rangeMinutes)
   const tickEvery = Math.max(1, Math.ceil(data.length / 6))
 
-  const chart = (
-    <div className="flex flex-col gap-4">
+  const hasData = data.some(point => point.rx !== null || point.tx !== null)
+  const chart = !hasData ? (
+    <p role="status" className="flex min-h-[220px] items-center justify-center text-sm text-muted-foreground">Нет исторических измерений за выбранный период</p>
+  ) : (
+    <div role="region" aria-label="История RX/TX" className="flex flex-col gap-4">
       <ChartContainer config={chartConfig} className="-ms-4 aspect-auto h-[220px] w-full">
         <LineChart data={data} margin={{ top: 5, right: 5, left: 5, bottom: 5 }}>
           <CartesianGrid