Add workflow support and enhance runtime configuration in models and services

- Introduce RuntimeModelResource and RuntimeKnowledgeBase classes to manage workflow resources.
- Update AssistantConfig to include workflow_model_resources and workflow_knowledge_bases for better integration.
- Refactor validation and processing logic in routes and services to accommodate workflow types.
- Implement dynamic variable support for workflow assistants and enhance graph normalization.
- Add ToolExecutor for reusable tool execution across different assistant types.
- Update various services to ensure compatibility with new workflow features and improve error handling.

frontend/src/lib/api.ts

@@ -11,6 +11,35 @@ export const API_BASE =
   process.env.NEXT_PUBLIC_API_BASE_URL ?? "http://localhost:8000";
 
 export type ModelType = "LLM" | "ASR" | "TTS" | "Realtime" | "Embedding" | "Agent";
+
+function formatErrorDetail(detail: unknown): string | null {
+  if (typeof detail === "string") return detail;
+  if (Array.isArray(detail)) {
+    const messages = detail
+      .map((item) => {
+        if (!item || typeof item !== "object") return null;
+        const record = item as { loc?: unknown; msg?: unknown };
+        const message = typeof record.msg === "string" ? record.msg : null;
+        if (!message) return null;
+        const path = Array.isArray(record.loc)
+          ? record.loc
+              .filter((part) => part !== "body")
+              .map(String)
+              .join(".")
+          : "";
+        return path ? `${path}：${message}` : message;
+      })
+      .filter((message): message is string => Boolean(message));
+    return messages.length ? messages.join("；") : null;
+  }
+  if (detail && typeof detail === "object") {
+    const record = detail as { message?: unknown; msg?: unknown };
+    if (typeof record.message === "string") return record.message;
+    if (typeof record.msg === "string") return record.msg;
+  }
+  return null;
+}
+
 async function request<T>(path: string, init?: RequestInit): Promise<T> {
   const isFormData = init?.body instanceof FormData;
   const res = await fetch(`${API_BASE}${path}`, {
@@ -30,8 +59,8 @@ async function request<T>(path: string, init?: RequestInit): Promise<T> {
   if (!res.ok) {
     let detail = `请求失败 (${res.status})`;
     try {
-      const body = (await res.json()) as { detail?: string };
-      if (body?.detail) detail = body.detail;
+      const body = (await res.json()) as { detail?: unknown };
+      detail = formatErrorDetail(body?.detail) ?? detail;
     } catch {
       // 响应体不是 JSON,沿用默认错误信息
     }