修复时间轴前进、后退范围bug

src/components/olmap/HealthRiskAnalysis/Timeline.tsx

@@ -177,7 +177,7 @@ const Timeline: React.FC<TimelineProps> = ({
   const handleStepBackward = useCallback(() => {
     setCurrentYear((prev: number) => {
       let next = prev - 1;
-      if (next < minTime) next = maxTime;
+      if (next < minTime) next += maxTime - minTime + 1;
       return next;
     });
   }, [minTime, maxTime]);