Cluster shards rebalance should take into account that primary shards are evenly distributed among the dataNodes

[kkewwei]

Describe the feature

When we wan to add some nodes to cluster, We use index.routing.allocation.total_shards_per_node to controll shards allocation. After reaching equilibrium, the primary shards are almost distributed on the new nodes, this is not a good phenomenon. there will be more pressure on the new nodes when indexing and recovery.

If we should add a new AllocationDecider to make distribution of the primary shards more evenly.

[DaveCTurner]

Closing this as a duplicate of #41543.