Currently in the Cloud -> Graph view there is a legend with color codes, but that is for replicas only.
We need a way to quickly see the state of the shard, in particular if it is active or inactive. For testing, create a collection, then call SPLITSHARD on shard1, and you'll end up with shards shard1, shard1_0 and shard1_1. It is not possible to see which one is active or inactive.
Also, the replicas belonging to the inactive shard are still marked with green "Active", while in reality they are "Inactive".
The simplest would be to add a new state "Inactive" with color e.g. blue, which would be used on both shard and replica level. But since an inactive replica could also be "Gone" or "Down", there should be some way to indicate both at the same time...