Enable use of PlantUML diagrams throughout Aha!

Who would benefit?

Everyone who needs to draw complex diagrams (many types are supported by PlantUML) and prefers an easy-to-maintain textual representation

For users migrating requirements from other platforms (e.g. Confluence), who are already using PlantUML, this would massively ease the migration

What impact would it make?

Far faster to maintain diagrams in this way

Far faster to migrate such diagrams from other platforms

How should it work?

Anywhere today where there is an option to add a diagram, PlantUML should be an option (whether directly or through a notebook/ whiteboard.)
This is supported in many such systems, including Confluence, Google Docs, directly in diagram.io (later version than supported by Aha!), etc.