Support for Mermaid swimlane beta diagrams

• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Is your feature request related to a problem? Please describe. No, it's a request to support a new feature

Describe the solution you'd like Mermaid has introduced swimlane in its beta selection of graphs from 11.16.0 It contains mostly the same elements as flowchart, though the subgraphs are lanes rather than floating boxes

Describe alternatives you've considered Conversion to flowchart, then manually arranging the swimlanes. Draw.io's strength is the ability to rearrange a mermaid diagram, which is the goal here. For complex flows arranging into swimlanes is time consuming

Additional context Nil