### 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
impacts.add(
                    new HealthIndicatorImpact(
                        NAME,
                        PRIMARY_UNASSIGNED_IMPACT_ID,
                        1,
                        impactDescription,
                        List.of(ImpactArea.INGEST, ImpactArea.SEARCH)
                    )
                );
            }
            /*
             * It is possible that we're working with an intermediate cluster state, and that for an index we have no primary but a replica
             * that is reported as unavailable. That replica is likely being promoted to primary. The only impact that matters at this
             * point is the one above, which has already been reported for this index.
             */
            Set<String> indicesWithUnavailableReplicasOnly = new HashSet<>(replicas.indicesWithUnavailableShards);
            indicesWithUnavailableReplicasOnly.removeAll(primaries.indicesWithUnavailableShards);
            if (indicesWithUnavailableReplicasOnly.isEmpty() == false) {
                String impactDescription = String.format(
                    Locale.ROOT,
                    "Searches might be slower than usual. Fewer redundant copies of the data exist on %d %s [%s].",
                    indicesWithUnavailableReplicasOnly.size(),
                    indicesWithUnavailableReplicasOnly.size() == 1 ? "index" : "indices",
                    getTruncatedIndices(indicesWithUnavailableReplicasOnly, clusterMetadata)
                );
                impacts.add(
                    new HealthIndicatorImpact(NAME, REPLICA_UNASSIGNED_IMPACT_ID, 2, impactDescription, List.of(ImpactArea.SEARCH))
                );
            }
            return impacts;