Auto-generated separate reference pages for Julia objects / docstrings

[mortenpi]

Originally mentioned in #212, but in light of @odow's work in jump-dev/JuMP.jl#3386, I think this deserves a dedicated issue.

Have function, type, module etc. reference as a separate set of pages, one item per page. Every item would then have a systematic URL (e.g. /reference/Documents/Page) to page that would contain the docstring, but also additional information (source links, lists of methods etc).

I think this is definitely a feature that should be explored, to nudge people towards more thorough docstrings etc.

One thing we could also do is generate backlinks from those reference pages to (1) where the docstring is referenced with at-ref, and (2) if we simultaneously allow including the docstrings in-line (related: #1079), we should also backlink to those.

I do think this should be done, in the first iteration, as a plugin package. Once that stabilizes, we could integrate it into Documenter-proper.

[fredrikekre]

Xref JuliaLang/julia#29552

[mortenpi]

Also mentioned in https://discourse.julialang.org/t/generate-structured-documentation/99247 and worth noting that Pollen.jl has this feature.

[odow]

Adding some screenshots from https://fluxml.ai/FastAI.jl/dev/FastAI@dev/ref/FastAI.html.

I like the table of symbols sorted by type. And the backlink feature. Makes it easy to see where that function is used in the documentation.

[odow]

See #443 for some other suggestions.