feat: 完善 Mermaid 配置与预览缩放

apps/web/src/paged-document-runtime.ts

@@ -131,9 +131,12 @@ export class PagedDocumentRuntime {
 
   private loadMermaid() {
     if (!this.mermaidPromise) {
-      this.mermaidPromise = import("mermaid").then(
-        ({ default: mermaid }) => {
-          mermaid.initialize(createMermaidSiteConfig());
+      this.mermaidPromise = Promise.all([
+        import("mermaid"),
+        import("@mermaid-js/layout-elk")
+      ]).then(
+        ([{ default: mermaid }, { default: elkLayouts }]) => {
+          mermaid.registerLayoutLoaders(elkLayouts);
           return mermaid;
         }
       );
@@ -160,6 +163,9 @@ export class PagedDocumentRuntime {
     }
 
     const mermaid = await this.loadMermaid();
+    mermaid.initialize(
+      createMermaidSiteConfig(payload.exportConfig.mermaid)
+    );
     const outcomes = await renderMermaidDefinitions(
       nodes.map((node) => node.textContent ?? ""),
       async (definition) => {