Addresses PR comments

Signed-off-by: Darshit Chanpura <dchanp@amazon.com>

Author: DarshitChanpura

src/main/java/org/opensearch/ad/model/AnomalyDetector.java

@@ -242,7 +242,7 @@ public AnomalyDetector(
 
     @Override
     public String getName() {
-        return "detector";
+        return "anomaly_detector";
     }
 
     @Override

src/main/java/org/opensearch/ad/transport/IndexAnomalyDetectorTransportAction.java

@@ -143,6 +143,8 @@ private void resolveUserAndExecute(
         Consumer<AnomalyDetector> function
     ) {
         try {
+            // Check if user has backend roles
+            // When filter by is enabled, block users creating/updating detectors who do not have backend roles.
             if (filterByEnabled) {
                 String error = checkFilterByBackendRoles(requestedUser);
                 if (error != null) {