Fix Prometheus metrics prefix

Most default Prometheus or Prometheus-like systems reject metrics names that don't match `[a-zA-Z_:][a-zA-Z0-9_:]*`

Author: m3diumrare

utils/metrics/metrics_util.go

@@ -17,7 +17,7 @@ import (
 )
 
 func SetupOtelMetricsProvider() error {
-	metricsExporter, err := prometheus.New(prometheus.WithNamespace("sei-chain"))
+	metricsExporter, err := prometheus.New(prometheus.WithNamespace("sei_chain"))
 	if err != nil {
 		return fmt.Errorf("failed to create Prometheus exporter: %w", err)
 	}