fix: improve chart tooltips

components/charts/snapshot-chart.tsx

@@ -2,6 +2,7 @@
 
 import { Bar, BarChart, Cell, ResponsiveContainer, Tooltip, XAxis, YAxis } from "recharts";
 import type { SynopStation } from "@/types/imgw";
+import { ChartTooltip } from "@/components/charts/chart-tooltip";
 import { Card } from "@/components/ui/card";
 import { useI18n } from "@/lib/i18n";
 import { useWeatherStore } from "@/lib/store";
@@ -56,7 +57,14 @@ export function SnapshotChart({ station }: { station: SynopStation }) {
             />
             <Tooltip
               cursor={{ fill: "hsl(var(--border) / 0.22)" }}
-              formatter={(_, __, item) => [`${item.payload.value} ${item.payload.unit}`, item.payload.name]}
+              content={
+                <ChartTooltip
+                  valueFormatter={(entry) => {
+                    const row = entry.payload;
+                    return `${row?.value ?? "—"} ${row?.unit ?? ""}`.trim();
+                  }}
+                />
+              }
             />
             <Bar dataKey="normalized" radius={[0, 8, 8, 0]} barSize={14}>
               {rows.map((row) => (