fix type conversion error

router/handlers/simulation.go

@@ -486,7 +486,7 @@ func buildSuccessURL(levelName string, score int, metrics map[string]interface{}
 		fmt.Sprintf("level=%s", levelName),
 		fmt.Sprintf("score=%d", score),
 		fmt.Sprintf("targetRPS=%d", targetRPS),
-		fmt.Sprintf("achievedRPS=%d", int(metrics["throughput"].(float64))),
+		fmt.Sprintf("achievedRPS=%d", metrics["throughput"].(int)),
 		fmt.Sprintf("targetLatency=%d", targetLatency),
 		fmt.Sprintf("actualLatency=%.1f", metrics["latency_avg"].(float64)),
 		fmt.Sprintf("availability=%.1f", metrics["availability"].(float64)),
@@ -532,7 +532,7 @@ func buildFailureURL(levelName string, metrics map[string]interface{}, feedback
 		fmt.Sprintf("level=%s", levelName),
 		fmt.Sprintf("reason=performance"),
 		fmt.Sprintf("targetRPS=%d", targetRPS),
-		fmt.Sprintf("achievedRPS=%d", int(metrics["throughput"].(float64))),
+		fmt.Sprintf("achievedRPS=%d", metrics["throughput"].(int)),
 		fmt.Sprintf("targetLatency=%d", targetLatency),
 		fmt.Sprintf("actualLatency=%.1f", metrics["latency_avg"].(float64)),
 		fmt.Sprintf("targetAvail=%.1f", targetAvail),