[FIX/BE] add clamp maximum value

internal/modules/dashboards/services/dashboard.service.go

@@ -625,7 +625,7 @@ func higherIsBetterPercent(actual map[int]map[uint]float64, week int, seriesId u
 	if !ok || val <= 0 {
 		return 0, false
 	}
-	return (val / standard) * 100, true
+	return clampPercent((val / standard) * 100), true
 }
 
 func lowerIsBetterPercent(actual map[int]map[uint]float64, week int, seriesId uint, standard float64) (float64, bool) {
@@ -636,7 +636,7 @@ func lowerIsBetterPercent(actual map[int]map[uint]float64, week int, seriesId ui
 	if !ok || val <= 0 {
 		return 0, false
 	}
-	return (standard / val) * 100, true
+	return clampPercent((standard / val) * 100), true
 }
 
 func metricValue(actual map[int]map[uint]float64, week int, seriesId uint) (float64, bool) {
@@ -648,6 +648,16 @@ func metricValue(actual map[int]map[uint]float64, week int, seriesId uint) (floa
 	return val, ok
 }
 
+func clampPercent(value float64) float64 {
+	if value < 0 {
+		return 0
+	}
+	if value > 200 {
+		return 200
+	}
+	return value
+}
+
 func buildComparisonAggregateChart(seriesRows []repository.ComparisonSeries, weeks []int, actual map[int]map[uint]float64) dto.DashboardChartDTO {
 	series := make([]dto.DashboardChartSeriesDTO, 0, len(seriesRows))
 	for _, sRow := range seriesRows {