✨ Feat: enhance Mermaid configuration and fix initialization bug (#617)

* 🐛 Fix: Mermaid initialization conflict error

* ✨ Feat: enhance Mermaid configuration with security level, look, and font family options

assets/js/lib/mermaid.js

@@ -0,0 +1,10 @@
+{{- $mermaid := .Param "mermaid" -}}
+{{- $mermaidCDN := $mermaid.cdn | default "https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.esm.min.mjs" -}}
+
+import mermaid from "{{ $mermaidCDN }}";
+{{- with $mermaid.zenuml }}
+import zenuml from "{{ . }}";
+await mermaid.registerExternalDiagrams([zenuml]);
+{{- end }}
+mermaid.startOnLoad = false;
+window.mermaid = mermaid;