Access to nested YAML front matter in listings sort:

[NeuroShepherd]

Description

It is not currently possible to use nested YAML parameters in the sort: option for listings. E.g. the following sort of documents in posts would not be respected:

posts/example_file1.qmd

title: Example
display_weight:
  - management: 2
  - staff: 10

posts/example_file2.qmd

title: Example
display_weight:
  - management: 1
  - staff: 16

listings_page.qmd

listing:
  - id: management
  - contents: posts
  - sort: "display_weight.management"

I recognize that separate top-level fields such as display_weight_management or similar could be created, but allowing access to the sub-fields allows for better organization.

[NeuroShepherd]

Adjacent to this now-implemented request: https://github.com/orgs/quarto-dev/discussions/6777