Handles all Markdig.Syntax.FencedCodeBlock nodes. Mermaid blocks are rendered
to SVG via Mermaider.MermaidRenderer (pure .NET, no browser required);
non-mermaid fenced blocks are rendered as styled code blocks and respect any
CodeHighlighter registered by the SyntaxHighlighting extension.
While IsProvisional(MarkdownObject) holds for a block (it contains the end of the text
being streamed), a Mermaid fence is rendered as a mermaid code block and no diagram render is
scheduled; it renders as a diagram once a blank line or another block follows it.
A diagram renders as soon as it comes within a screen of the viewport. Where threads are available (not in the
browser), every diagram also starts rendering in the background once it is in a window, so that scrolling
to it later costs nothing.
With IsImageZoomEnabled, clicking a rendered diagram opens it in the viewer's
lightbox, as an image, where it is fitted to the view and can be zoomed and panned.
public MermaidBlockRenderer(MermaidStyle style = MermaidStyle.Quiet)
The visual style diagrams are painted in.