Update quad chart with mermaid

[brownsarahm]

I have not tested this with varnish yet and there may be an issue with the alt text so that needs to be addressed, but this is a start!

closes #1801

[github-actions]

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⏱️ Updated at 2026-06-04 00:32:54 +0000

[ndporter]

I built this locally to check the charts and some of the text on the parking one is off the chart, literally. See image.

[ndporter]

There are also some caption and/or alt-text issues to fix, and I'm submitting something to workbench to fix contrast on source code. But once the diagram is fixed, we can work on those.