feat: AI 对话支持 A2UI 表单/审查/图表与 Agent 工具

apps/admin/src/components/AiChat/LiteMermaid.tsx

@@ -0,0 +1,48 @@
+import { useEffect, useRef, useState } from 'react';
+
+interface LiteMermaidProps {
+  children: string;
+}
+
+/**
+ * 轻量 Mermaid 渲染：动态 import mermaid，只有出现 mermaid 代码块时才加载
+ * mermaid 及其解析器/图布局依赖，避免随 AI 抽屉主包一起加载。
+ */
+export function LiteMermaid({ children }: LiteMermaidProps) {
+  const containerRef = useRef<HTMLDivElement>(null);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    let cancelled = false;
+    const container = containerRef.current;
+    if (!container) return;
+
+    void (async () => {
+      try {
+        const mermaid = (await import('mermaid')).default;
+        mermaid.initialize({ startOnLoad: false, theme: 'neutral', securityLevel: 'strict' });
+        const { svg } = await mermaid.render(`mermaid-${crypto.randomUUID()}`, children);
+        if (!cancelled) {
+          const doc = new DOMParser().parseFromString(svg, 'image/svg+xml');
+          container.replaceChildren(doc.documentElement);
+          setError(null);
+        }
+      } catch (e) {
+        if (!cancelled) {
+          setError(e instanceof Error ? e.message : '图表渲染失败');
+        }
+      }
+    })();
+
+    return () => {
+      cancelled = true;
+    };
+  }, [children]);
+
+  if (error) {
+    return (
+      <pre style={{ whiteSpace: 'pre-wrap', color: '#cf1322', fontSize: 12 }}>{children}</pre>
+    );
+  }
+  return <div ref={containerRef} className="ai-chat-mermaid" />;
+}