### Elasticsearch Version

8.1.2

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

ESS on Azure

### Problem Description

The `_xpack/usage` API reports the size of the data set per data tier. However, it uses the local disk size as the metric it reports on and this is 0 (zero) for partially mounted indices, hiding the size of the data set mounted on the frozen tier.

We should switch to using the `total_data_set_size` metric that was introduced when we added the frozen tier/partially mounted indices.

### Steps to Reproduce

Mount a partially mounted index on a dedicated frozen tier. Use the `_xpack/usage` API and see that no (or very little) data is reported on frozen tier.

### Logs (if relevant)

_No response_
x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/DataTiersUsageTransportActionTests.java
assertThat(tierSpecificStats.size(), is(0));
    }
    public void testCalculateStatsTieredNodesOnly() {
        
        DiscoveryNodes.Builder discoBuilder = DiscoveryNodes.builder();
        DiscoveryNode leader = newNode(0, DiscoveryNodeRole.MASTER_ROLE);
        discoBuilder.add(leader);
        discoBuilder.masterNodeId(leader.getId());
        DiscoveryNode dataNode1 = newNode(1, DiscoveryNodeRole.DATA_ROLE);
        discoBuilder.add(dataNode1);
        DiscoveryNode hotNode1 = newNode(2, DiscoveryNodeRole.DATA_HOT_NODE_ROLE);
        discoBuilder.add(hotNode1);
        DiscoveryNode warmNode1 = newNode(3, DiscoveryNodeRole.DATA_WARM_NODE_ROLE);
        discoBuilder.add(warmNode1);
        DiscoveryNode coldNode1 = newNode(4, DiscoveryNodeRole.DATA_COLD_NODE_ROLE);
        discoBuilder.add(coldNode1);
        DiscoveryNode frozenNode1 = newNode(5, DiscoveryNodeRole.DATA_FROZEN_NODE_ROLE);
        discoBuilder.add(frozenNode1);
        discoBuilder.localNodeId(dataNode1.getId());
        
        Metadata.Builder metadataBuilder = Metadata.builder();
        RoutingTable.Builder routingTableBuilder = RoutingTable.builder();
        IndexMetadata index1 = indexMetadata("index_1", 3, 1);
        metadataBuilder.put(index1, false).generateClusterUuidIfNeeded();
        {
            IndexRoutingTable.Builder indexRoutingTableBuilder = IndexRoutingTable.builder(index1.getIndex());
            routeTestShardToNodes(index1, 0, indexRoutingTableBuilder, dataNode1);
            routeTestShardToNodes(index1, 1, indexRoutingTableBuilder, dataNode1);
            routeTestShardToNodes(index1, 2, indexRoutingTableBuilder, dataNode1);
            routingTableBuilder.add(indexRoutingTableBuilder.build());