Register setting cluster.indices.tombstones.size (#26193)

The node setting `cluster.indices.tombstones.size` was not registered with the settings infrastructure, making it impossible for it to be set by a user.

Closes #26191

core/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java

@@ -31,6 +31,7 @@ import org.elasticsearch.cluster.ClusterName;
 import org.elasticsearch.cluster.InternalClusterInfoService;
 import org.elasticsearch.cluster.NodeConnectionsService;
 import org.elasticsearch.cluster.action.index.MappingUpdatedAction;
+import org.elasticsearch.cluster.metadata.IndexGraveyard;
 import org.elasticsearch.cluster.metadata.MetaData;
 import org.elasticsearch.cluster.routing.allocation.DiskThresholdSettings;
 import org.elasticsearch.cluster.routing.allocation.allocator.BalancedShardsAllocator;
@@ -402,6 +403,7 @@ public final class ClusterSettings extends AbstractScopedSettings {
                     SearchModule.INDICES_MAX_CLAUSE_COUNT_SETTING,
                     ThreadPool.ESTIMATED_TIME_INTERVAL_SETTING,
                     FastVectorHighlighter.SETTING_TV_HIGHLIGHT_MULTI_VALUE,
-                    Node.BREAKER_TYPE_KEY
+                    Node.BREAKER_TYPE_KEY,
+                    IndexGraveyard.SETTING_MAX_TOMBSTONES
             )));
 }

core/src/test/java/org/elasticsearch/gateway/GatewayIndexStateIT.java

@@ -29,6 +29,7 @@ import org.elasticsearch.action.support.ActiveShardCount;
 import org.elasticsearch.client.Client;
 import org.elasticsearch.client.Requests;
 import org.elasticsearch.cluster.ClusterState;
+import org.elasticsearch.cluster.metadata.IndexGraveyard;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.metadata.MappingMetaData;
 import org.elasticsearch.cluster.metadata.MetaData;
@@ -331,7 +332,8 @@ public class GatewayIndexStateIT extends ESIntegTestCase {
 
         final List<String> nodes;
         logger.info("--> starting a cluster with " + numNodes + " nodes");
-        nodes = internalCluster().startNodes(numNodes);
+        nodes = internalCluster().startNodes(numNodes,
+            Settings.builder().put(IndexGraveyard.SETTING_MAX_TOMBSTONES.getKey(), randomIntBetween(10, 100)).build());
         logger.info("--> create an index");
         createIndex(indexName);