Is your feature request related to a problem? Please describe.

Not necessarily a problem at the moment, but possibly an opportunity for improvement.

Describe the solution you'd like

The Doclet creates many distinct (independent) diagrams, that could easily be created in parallel to each other.

Keep the diagram creation itself as it is, since there might be concurrency issues due to the mutability of uml model classes.

Describe alternatives you've considered

Parallelizing everything at once, but this would require making the entire UML package threadsafe which honestly seems too much effort at this point in time. Let's first see how much concurrent diagram creation helps in the total build time.

Additional context