Add zoom and pan to mermaid diagrams on the docs website

Follow-up from #1168 (comment 1359354654)

As a documentation reader, it would be helpful to be able to zoom and pan around mermaid diagrams. This would especially benefit anyone trying to read a very large diagram.

Mermaid does not provide this in mermaid.js currently, but they do include it as an option in the live editor. Ideally this is doable without loading the entirety of d3.js on the frontend.

Links:

• https://jsfiddle.net/zu_min_com/2agy5ehm/26/
• https://github.com/mermaid-js/mermaid/issues/1860
• https://github.com/mermaid-js/mermaid/issues/2162
• https://github.com/corentinleberre/docsify-mermaid-zoom (we do not use Docsify but I bet there's something to be learned from their implementation)