Alternative PlantUML implementation

What does this MR do and why?

Alternative PlantUML implementation

Rather than bringing in random implementations which have questionable licenses, we could rely on browser APIs.

Screenshots, screen recordings, or links to review app

See !96 (merged)

How to set up and validate locally

See !96 (merged)

Merge request acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this merge request.