Increase node list field in VS node selection

### Describe the project you are working on

Would apply to any visual scripting project

### Describe the problem or limitation you are having in your project

The frame for the node list is very small and makes browsing awkward, as of now it's possible to increase the size by dragging the top of the window, but it makes a really tall window and it is restored every time it gets closed and re-opened.

### Describe the feature / enhancement and how it helps to overcome the problem or limitation

Increase the height of the node list frame and make the separator between nodes list and description draggable and persistent.

### Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

By default the window could be divided 50/50 (or 70/30 since most nodes don't have a description). It's possible to drag the horizontal separator and the change should be permanent, without needing to change it every time.

### If this enhancement will not be used often, can it be worked around with a few lines of script?

Possibly

### Is there a reason why this should be core and not an add-on in the asset library?

It is a simple edit that shouldn't need an external add-on.