### Description

It should be enough to have ShardId + nodeId key in `routingToDataPath` to find the necessary data path. 
Changing the key would allow us to minimize the size of ClusterInfo size and find the data path when shard changes its status.

`ClusterInfo` might be sent over the wire when cluster allocation explain is executed with `includeDiskInfo=true`.
ShardRouting -> ShardId + nodeId conversion is trivial. The oposit would require additional information that could be faked.

Current key is also used in here:
https://github.com/elastic/elasticsearch/blob/9ebbe1c62bf0157d332f20f392544a1921a710df/server/src/main/java/org/elasticsearch/cluster/ClusterInfo.java#L149-L154
where it produces a string with ShardRouting#shortSummary that is excessive and might be simplified to ShardId + nodeId as well
server/src/test/java/org/elasticsearch/cluster/ClusterInfoTests.java
Map<String, DiskUsage> builder = new HashMap<>(numEntries);
        for (int i = 0; i < numEntries; i++) {
            String key = randomAlphaOfLength(32);
            DiskUsage diskUsage = new DiskUsage(
                randomAlphaOfLength(4),
                randomAlphaOfLength(4),
                randomAlphaOfLength(4),
                randomIntBetween(0, Integer.MAX_VALUE),
                randomIntBetween(0, Integer.MAX_VALUE)
            );
            builder.put(key, diskUsage);
        }
        return builder;
    }
    private static Map<String, Long> randomShardSizes() {
        int numEntries = randomIntBetween(0, 128);
        Map<String, Long> builder = new HashMap<>(numEntries);
        for (int i = 0; i < numEntries; i++) {
            String key = randomAlphaOfLength(32);
            long shardSize = randomIntBetween(0, Integer.MAX_VALUE);
            builder.put(key, shardSize);
        }
        return builder;
    }
    private static Map<ShardId, Long> randomDataSetSizes() {
        int numEntries = randomIntBetween(0, 128);
        Map<ShardId, Long> builder = new HashMap<>(numEntries);
        for (int i = 0; i < numEntries; i++) {
            ShardId key = new ShardId(randomAlphaOfLength(10), randomAlphaOfLength(10), between(0, Integer.MAX_VALUE));
            long shardSize = randomIntBetween(0, Integer.MAX_VALUE);