use https://github.com/nunocoracao/blowfish.git

themes/blowfish/assets/lib/mermaid/diagram-api/frontmatter.d.ts

@@ -0,0 +1,18 @@
+import type { MermaidConfig } from '../config.type.js';
+interface FrontMatterMetadata {
+    title?: string;
+    displayMode?: string;
+    config?: MermaidConfig;
+}
+export interface FrontMatterResult {
+    text: string;
+    metadata: FrontMatterMetadata;
+}
+/**
+ * Extract and parse frontmatter from text, if present, and sets appropriate
+ * properties in the provided db.
+ * @param text - The text that may have a YAML frontmatter.
+ * @returns text with frontmatter stripped out
+ */
+export declare function extractFrontMatter(text: string): FrontMatterResult;
+export {};