### Elasticsearch Version

8.8.1+ but probably all versions

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

cloud

### Problem Description

This is a follow-up of [#97370](https://github.com/elastic/elasticsearch/issues/97370). 

In a case where disk spaces are reaching limits, if ILM suddenly tries to move a lot of hot shards to cold/frozen shards, it can tip the cluster health to RED because a lot of cold/frozen shards may be created and stay unassigned as long as there is not enough disk space. However, this is not a suitable indicator for service unavailability, since the data is still safely in the respective hot shards that are becoming cold/frozen, and will remain there until the cold/frozen shards are assigned so that searches can still search them.

Thus the [Health Report API](https://www.elastic.co/guide/en/elasticsearch/reference/8.8/health-api.html) should not return RED for unassigned cold/frozen shards of ILM moves.

### Steps to Reproduce

In a case where disk spaces are reaching limits, if ILM suddenly tries to move a lot of hot shards to cold/frozen shards, it can tip the cluster health to RED because a lot of cold/frozen shards may be created and stay unassigned (as long as there is not enough disk space).

### Logs (if relevant)

_No response_
server/src/main/java/org/elasticsearch/cluster/routing/allocation/ShardsAvailabilityHealthIndicatorService.java
SystemIndices.Feature::getName,
                        feature -> feature.getDataStreamDescriptors()
                            .stream()
                            .flatMap(descriptor -> descriptor.getBackingIndexNames(metadata).stream())
                            .collect(toSet())
                    )
                );
            
            
            for (Map.Entry<String, Set<String>> featureToBackingIndices : featureToDsBackingIndices.entrySet()) {
                for (String featureIndex : featureToBackingIndices.getValue()) {
                    if (restoreFromSnapshotIndices.contains(featureIndex)) {
                        affectedFeatureStates.add(featureToBackingIndices.getKey());
                        affectedIndices.remove(featureIndex);
                    }
                }
            }
            if (affectedIndices.isEmpty() == false) {
                affectedResources.add(new Diagnosis.Resource(INDEX, affectedIndices.stream().limit(maxAffectedResourcesCount).toList()));
            }
            if (affectedFeatureStates.isEmpty() == false) {
                affectedResources.add(
                    new Diagnosis.Resource(FEATURE_STATE, affectedFeatureStates.stream().limit(maxAffectedResourcesCount).toList())
                );
            }
            return affectedResources;
        }
    }
}