[GSP-4] Generate _per statement_ type diagrams to be used in the spec docs.

[carsonfarmer]

Ideally, as SVG, but could be PNG. Just need a way to be able to reference specific (sets of) diagrams in the docs markdown files.

_GSP-4

[sanderpick]

@carson this one too. For context, these issues got pulled into linear via the "linear" label. Whey they land in linear, they show up as "triage". So, the goal is to do the triage… move them to backlog if we're going to address them at some point / cancel them.