Add ability to choose only specific nodes from the metrics dropdown menu

[daniel-crlabs]

Is your feature request related to a problem? Please describe.

Currently we can pick either all nodes from the Metrics menu, by choosing the Graph:Cluster option or we can choose one single node by choosing that particular node from the dropdown menu:

Describe the solution you'd like

It would be great to be able to choose specific nodes (more than one, but not all nodes -- example, 2 nodes out of 15) when choosing which nodes to display the information in the Metrics graphs. This is particularly handy when troubleshooting very large clusters (i.e. a cluster with 15 nodes) and you are only interested in a few nodes in particular. It would be great to choose the few nodes you want to troubleshoot, instead of having to populate the graphs with data for all nodes, when you are only interested in a few. At the moment, we have to select either one node at a time, or all nodes.

Describe alternatives you've considered

There is no alternative.

Additional context

Being able to select specific nodes from the drop down like the example below would be ideal. I'm not a graphic artist, but the image below should give you an idea, assume I wanted to only see the metrics for nodes 1 and 3, I should be able to pick only those 2 nodes from the drop down shown in the picture below:

Jira issue: CRDB-19195

Epic CRDB-32130

[daniel-crlabs]

It's been over 1 year since I created this request, yet, it hasn't been touched. This continues to be a problem when trying to troubleshoot clusters with multiple nodes, latest example below, this cluster has over 60 noes and it is impossible to see the legends. As you see below, it is impossible to compare all nodes (this cluster has 66, but only a few can be seen)