Add Export to Mermaid/DrawIO to bicep visualizer export process

[ChrisLewis3Cloud]

Shenglong Li demoed the new Bicep Visualizer functionality in the March community call on 4/1.

Currently, the only supported export format is PNG.

Adding Mermaid and DrawIO export would be extremely useful for further refining diagrams for documentation, such as adding grouping boxes and labels. This would also be extremely useful for Diagram as Code functionality and checking in documentation into source control.