### Description

Elasticsearch defines the concept of a [feature](https://www.elastic.co/guide/en/elasticsearch/reference/current/get-features-api.html) for the purpose of better managing them when snapshotting/restoring them via the [feature_states field](https://www.elastic.co/guide/en/elasticsearch/reference/current/create-snapshot-api.html#create-snapshot-api-feature-states)

The `shards_availability` health indicator currently diagnoses the condition of indices needing to be [restored from a snapshot](https://github.com/elastic/elasticsearch/blob/main/server/src/main/java/org/elasticsearch/cluster/routing/allocation/ShardsAvailabilityHealthIndicatorService.java#L138) and recommends a [troubleshooting guide](http://ela.st/restore-snapshot)

However, since `8.x` the restore API **must** use `feature_states` instead of specifying systems indices or system data streams as part of the `indices` field.

This proposes the `affected_resources` for the `restore_from_snapshot` diagnosis return the indices that are not part of a `feature` under the `INDICES` type, and a new type `FEATURES`.
e.g. instead of current behaviour
```
"affected_resources": {
  "indices": [
    ".geoip_databases",
    "test_index"
    ]
}
```
we could return:
```
"affected_resources": {
  "indices": [
    "test_index"
   ], 
  "features": [
     "geoip"
  ]
}
```



server/src/main/java/org/elasticsearch/node/Node.java
threadPool,
                        client,
                        settingsModule,
                        clusterModule.getIndexNameExpressionResolver()
                    )
                )
                .flatMap(List::stream)
                .collect(toList());
            final PersistentTasksExecutorRegistry registry = new PersistentTasksExecutorRegistry(
                concatLists(pluginTaskExecutors, builtinTaskExecutors)
            );
            final PersistentTasksClusterService persistentTasksClusterService = new PersistentTasksClusterService(
                settings,
                registry,
                clusterService,
                threadPool
            );
            resourcesToClose.add(persistentTasksClusterService);
            final List<ShutdownAwarePlugin> shutdownAwarePlugins = pluginsService.filterPlugins(ShutdownAwarePlugin.class);
            final PluginShutdownService pluginShutdownService = new PluginShutdownService(shutdownAwarePlugins);
            clusterService.addListener(pluginShutdownService);
            final RecoveryPlannerService recoveryPlannerService = getRecoveryPlannerService(threadPool, clusterService, repositoryService);
            final DesiredNodesSettingsValidator desiredNodesSettingsValidator = new DesiredNodesSettingsValidator(
                clusterService.getClusterSettings()
            );
            MasterHistoryService masterHistoryService = new MasterHistoryService(transportService, threadPool, clusterService);
            CoordinationDiagnosticsService coordinationDiagnosticsService = new CoordinationDiagnosticsService(
                clusterService,
                transportService,
                discoveryModule.getCoordinator(),