### Elasticsearch Version

8.4, 8.5, 8.6

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

Darwin

### Problem Description

The shards availability indicator should always be reporting diagnosis when its status is RED/YELLOW.
However, when an index is on a data node that runs out of disk space it will report RED but no diagnosis.

### Steps to Reproduce

Have multi-node cluster where a data (non-master) node that hosts an index runs out of disk space (the index cannot relocate somewhere else).
Call the Health API and the output will be something along these lines:
```
    "shards_availability": {
      "status": "red",
      "symptom": "This cluster has all shards available.",
      "details": {
        "initializing_primaries": 1,
        "started_replicas": 0,
        "initializing_replicas": 0,
        "unassigned_primaries": 0,
        "started_primaries": 1,
        "creating_primaries": 0,
        "unassigned_replicas": 0,
        "restarting_primaries": 0,
        "restarting_replicas": 0
      },
      "impacts": [
        {
          "id": "elasticsearch:health:shards_availability:impact:primary_unassigned",
          "severity": 1,
          "description": "Cannot add data to 1 index [test_index]. Searches might return incomplete results.",
          "impact_areas": [
            "ingest",
            "search"
          ]
        }
      ] 
    }
``` 

### Logs (if relevant)

_No response_
server/src/main/java/org/elasticsearch/cluster/routing/allocation/ShardsAvailabilityHealthIndicatorService.java
private static final Logger LOGGER = LogManager.getLogger(ShardsAvailabilityHealthIndicatorService.class);
    public static final String NAME = "shards_availability";
    private static final String DATA_TIER_ALLOCATION_DECIDER_NAME = "data_tier";
    private final ClusterService clusterService;
    private final AllocationService allocationService;
    private final SystemIndices systemIndices;
    public ShardsAvailabilityHealthIndicatorService(
        ClusterService clusterService,
        AllocationService allocationService,
        SystemIndices systemIndices
    ) {
        this.clusterService = clusterService;
        this.allocationService = allocationService;
        this.systemIndices = systemIndices;
    }
    @Override
    public String name() {
        return NAME;
    }
    @Override
    public HealthIndicatorResult calculate(boolean verbose, int maxAffectedResourcesCount, HealthInfo healthInfo) {
        var state = clusterService.state();
        var shutdown = state.getMetadata().custom(NodesShutdownMetadata.TYPE, NodesShutdownMetadata.EMPTY);