[2DC] Cluster

[Raubzeug]

Somewhere here:

we show information about "bridge" mode working on a cluster.

only when bridge mode is actually working.

to test it you can use capabilities handler:

the information we show is about "piles", when it is in /viewer/cluster response:

we want to show a brief table, consisting of:

1. Name of a pile
2. A flag whenever it's a primary
3. A state
4. Number of nodes

[astandrik]

@AlinaBelousovaUX would you design review this Stand please