fix(frontend): errorCode 统一自 generation/cards 去重复定义（CR-H10）

apps/web/lib/style/useStyleLearn.ts

@@ -6,6 +6,7 @@ import { api } from "@/lib/api/client";
 import { useToast } from "@/components/Toast";
 import { useJobPoll } from "@/lib/jobs/useJobPoll";
 import { styleLearnResult } from "@/lib/jobs/job";
+import { errorCode } from "@/lib/generation/cards";
 import {
   buildLearnRequest,
   normalizeFingerprint,
@@ -27,12 +28,6 @@ export interface UseStyleLearn {
   ) => Promise<boolean>;
 }
 
-function errorCode(error: unknown): string | undefined {
-  if (typeof error !== "object" || error === null) return undefined;
-  const env = error as { error?: { code?: unknown } };
-  return typeof env.error?.code === "string" ? env.error.code : undefined;
-}
-
 // 学文风编排：受理（202 job_id）→ useJobPoll 轮询 → done 拉 GET /style 展示指纹。
 export function useStyleLearn(initial: Fingerprint | null): UseStyleLearn {
   const [fingerprint, setFingerprint] = useState<Fingerprint | null>(initial);