Drop the mermaid import from the markdown module. The extension only emits <pre class="mermaid">, so initialize mermaid in the app entry instead. Use explicit .js specifiers plus a bundler extensionAlias so both the NodeNext CLI build and the web build resolve the sources.
Drop legacy yaml/tag info string; tag blocks now require
```yaml role=tag. Add fence-line tag=/id= attributes that
override YAML body values, and move parseBlockAttrs to
src/markdown/block-attrs.ts so scanner and render extensions
share one parser.
Accept yaml role=tag alongside legacy yaml/tag so the block
body gets yaml syntax highlighting, matching the CLI role=
attribute convention. Copy button now emits the role=tag form.
Allow md-deck layers to render markdown templates via {{var}}
substitution instead of only CSV props. Add config.ts to normalize
a JSON data-config attribute (size, grid, shape, layers) emitted by
the yaml code-block tag, taking precedence over legacy string props.
hypercross