Docs site improvements

[nrichers]

Internal Notes for Reviewers

This PR includes a number of incremental improvements for our docs site that came out of notebook testing in preparation for the closed beta. If this looks good to you, please approve and I will publish.

New dropdown for the Developer Framework that gives faster access to the most important bits, such as our code samples and the reference documentation:

Publication date info for each page that reflects the last time the source file was touched (intially, all files will show that they have been updates as they now all include last-modified but subsequent releases will make it much easier to see what was updated):

Previous/Next topic footers for related topics that makes it easy to keep reading:

Mermaid diagrams now use a lighter color to improve legibility, picked from the ValidMind palette (previously, they used a much darker pink which feels glaring after a while):

Toggle key concepts section to expand by default and add some additional info for tests.

External Release Notes

We made a number of incremental improvements to our user guide:

• New dropdown for the Developer Framework that gives faster access to the most important bits, such as our code samples and the reference documentation.
• Publication date for each page that reflects the last time the source file was touched.
• Previous and next topic footers** for related topics that make it easier to keep reading.
• Lighter background for diagrams that improves legibility.
• Expanded overview for key ValidMind concepts with some additional information.

[nrichers]

I made an additional change to this PR: I toggled the section with key concepts to be expanded by default. It seems people are missing that we have this section and expanding it by default solves this (at the expense of a slightly longer getting started section).

[nrichers]

During testing, I noticed that the CSS on the front page of our docs site interferes with the new "Developer Framework" drop-down. Need to investigate and fix before merging this PR.

[nrichers]

During testing, I noticed that the CSS on the front page of our docs site interferes with the new "Developer Framework" drop-down. Need to investigate and fix before merging this PR.

I traced this issue back to the Bootstrap JavaScript in site/assets/bootstrap/js/bootstrap.min.js that gets loaded at the bottom of the HTML page we embed as our main docs landing page. Commenting out that JavaScript solves the issue.

Looking at the code, it's possible that the embed of Popper JavaScript in that file is the cause, but I don't want to start modifying Bootstrap JavaScript code itself. This looks to be a case of overlapping functionality — dropdowns and tooltips we get from Quarto are also defined via Bootstrap and they interfere.

With the Bootstrap JavaScript disabled, I did some testing to make sure the page is still reactive (it is) and that it works in Chrome, Safari, and FireFox (it does).

Output

On the left is the current home page with JavaScript enabled, right is this pull request with JavaScript disabled running on localhost. They are near identical.