feat: stop jdaviz/voila when the browser window closes

[maartenbreddels]

Description

This feature closes jdaviz (voila) when a kernel closes, which should happen when a browser page/tab is closed.

Voila itself does not have this feature, although jupyter-server has something along these lines, but only polls every 60 seconds:
https://github.com/jupyter-server/jupyter_server/blob/de6d9047fa414859856198b7b2dfe80e60edd010/jupyter_server/serverapp.py#L2547

This change makes it immediate, but requires monkey patching. This API has been stable from the start of Voila when we wrote it, so I am not too worried that is will break, and I also believe Voila is pinned.

Checklist for package maintainer(s)

This checklist is meant to remind the package maintainer(s) who will review this pull request of some common things to look for. This list is not exhaustive.

• Are two approvals required? Branch protection rule does not check for the second approval. If a second approval is not necessary, please apply the trivial label.
• Do the proposed changes actually accomplish desired goals? Also manually run the affected example notebooks, if necessary.
• Do the proposed changes follow the STScI Style Guides?
• Are tests added/updated as required? If so, do they follow the STScI Style Guides?
• Are docs added/updated as required? If so, do they follow the STScI Style Guides?
• Did the CI pass? If not, are the failures related?
• Is a milestone set? Set this to bugfix milestone if this is a bug fix and needs to be released ASAP; otherwise, set this to the next major release milestone. Bugfix milestone also needs an accompanying backport label.
• After merge, any internal documentations need updating (e.g., JIRA, Innerspace)?

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 11 lines in your changes are missing coverage. Please review.

Project coverage is 88.71%. Comparing base (f1ba4a6) to head (920b616).
Report is 28 commits behind head on main.

Files	Patch %	Lines
jdaviz/cli.py	0.00%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2791      +/-   ##
==========================================
- Coverage   88.72%   88.71%   -0.01%     
==========================================
  Files         110      110              
  Lines       16353    16557     +204     
==========================================
+ Hits        14509    14689     +180     
- Misses       1844     1868      +24     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[pllim]

Tested on Windows 11. I launched CLI from a terminal. Able to use Imviz. When I closed the tab, the terminal got freed up, i.e., I didn't have to Control+C to get out of the server. So I think this works. Thanks!

[kecnry]

Maybe we should consider this a bugfix and get it in 3.9.1?

[rosteen]

I tested this successfully on Mac, I'm ok with the monkey patching to get this working. Thanks!

[kecnry]

rebased and added a changelog entry for 3.9.1. Should be good to merge as soon as CI runs/passes.