MAINT: have `qn_domains`-keys in Node/EdgeSettings be typed #571

Job	Run time
pytest / Determine job matrix	7s
style / Determine skipped pre-commit hooks	6s
doc / nb / Execute and build documentation	1m 16s
doc / linkcheck / Check external links	1m 1s
style / Run local pre-commit hooks	1m 7s
style / Run taplo through pre-commit	0s
pytest / Run unit tests (3.10, ubuntu-24.04)	1m 18s
pytest / Run unit tests (3.11, ubuntu-24.04)	1m 18s
pytest / Run unit tests (3.9, ubuntu-24.04)	1m 22s
pytest / Run unit tests (3.12, ubuntu-24.04, qrules)	4m 48s
pytest / Run unit tests (3.9, macos-14)	1m 5s
doc / Upload to GitHub Pages	0s
style / Push changes	0s
	13m 28s

Provide feedback