option to cull idle named servers only without interfering idle default servers

[HCharlie]

Proposed change

Hi, we have a use case in which we want to cull only the idle named servers without shutting down the idle default servers, could we make this configurable?

Alternative options

Who would use this feature?

For our use case, we provide a lot of small singleuser default servers running on cheap instances, and we don't want to cull them even if they are in idle state. And we also few named servers on expensive instances(for heavy workloads), and we want to cull these expensive servers when they are idle to avoid accidental cost.

(Optional): Suggest a solution

[welcome[bot]]

Thank you for opening your first issue in this project! Engagement like this is essential for open source projects! :hugs:
If you haven't done so already, check out Jupyter's Code of Conduct. Also, please try to follow the issue template as it helps other other community members to contribute more effectively. You can meet the other Jovyans by joining our Discourse forum. There is also an intro thread there where you can stop by and say Hi! :wave:
Welcome to the Jupyter community! :tada: