[ML] Add _cat/ml/anomaly_detectors API (#51364)

* [ML] Add _cat/ml/anomaly_detectors/_stats

* addressing PR feedback

Author: benwtrent

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/stats/ForecastStats.java

@@ -83,6 +83,30 @@ public ForecastStats merge(ForecastStats other) {
         return this;
     }
 
+    public long getTotal() {
+        return total;
+    }
+
+    public long getForecastedJobs() {
+        return forecastedJobs;
+    }
+
+    public StatsAccumulator getMemoryStats() {
+        return memoryStats;
+    }
+
+    public StatsAccumulator getRecordStats() {
+        return recordStats;
+    }
+
+    public StatsAccumulator getRuntimeStats() {
+        return runtimeStats;
+    }
+
+    public CountAccumulator getStatusCounts() {
+        return statusCounts;
+    }
+
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/MachineLearning.java

@@ -255,6 +255,7 @@
 import org.elasticsearch.xpack.ml.rest.calendar.RestPostCalendarEventAction;
 import org.elasticsearch.xpack.ml.rest.calendar.RestPutCalendarAction;
 import org.elasticsearch.xpack.ml.rest.calendar.RestPutCalendarJobAction;
+import org.elasticsearch.xpack.ml.rest.cat.RestCatJobsAction;
 import org.elasticsearch.xpack.ml.rest.datafeeds.RestDeleteDatafeedAction;
 import org.elasticsearch.xpack.ml.rest.datafeeds.RestGetDatafeedStatsAction;
 import org.elasticsearch.xpack.ml.rest.datafeeds.RestGetDatafeedsAction;
@@ -765,7 +766,9 @@ public List<RestHandler> getRestHandlers(Settings settings, RestController restC
             new RestGetTrainedModelsAction(restController),
             new RestDeleteTrainedModelAction(restController),
             new RestGetTrainedModelsStatsAction(restController),
-            new RestPutTrainedModelAction(restController)
+            new RestPutTrainedModelAction(restController),
+            // CAT Handlers
+            new RestCatJobsAction(restController)
         );
     }