### 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/main/java/org/elasticsearch/cluster/routing/ShardRouting.java
assert relocationFailureInfo != null : "relocation failure info must be always set";
        assert (state == ShardRoutingState.UNASSIGNED || state == ShardRoutingState.INITIALIZING) == (recoverySource != null)
            : "recovery source only available on unassigned or initializing shard but was " + state;
        assert recoverySource == null || recoverySource == PeerRecoverySource.INSTANCE || primary
            : "replica shards always recover from primary";
        assert (currentNodeId == null) == (state == ShardRoutingState.UNASSIGNED)
            : "unassigned shard must not be assigned to a node " + this;
        assert relocatingNodeId == null || state == ShardRoutingState.RELOCATING || state == ShardRoutingState.INITIALIZING
            : state + " shard must not have relocating node " + this;
    }
    @Nullable
    private ShardRouting initializeTargetRelocatingShard() {
        if (state == ShardRoutingState.RELOCATING) {
            return new ShardRouting(
                shardId,
                relocatingNodeId,
                currentNodeId,
                primary,
                ShardRoutingState.INITIALIZING,
                PeerRecoverySource.INSTANCE,
                unassignedInfo,
                RelocationFailureInfo.NO_FAILURES,
                AllocationId.newTargetRelocation(allocationId),
                expectedShardSize
            );
        } else {
            return null;
        }
    }
    /**