Structure panel: toggling "Show nested expressions" shouldn't expand nodes

[jfehrle]

plugin version: 0.124-2023.1

Description

Clicking on "Show nested expressions" can expand nodes in the structure tree. I think the expansion shouldn't change, particularly since currently you have to unexpand nodes one by one.

Before:

After:

class coqops
object(self)
  val script = _script
end