fix: harden generation task polling fallback

src/api/keyServerClient.ts

@@ -434,6 +434,7 @@ function normalizeUser(raw: unknown): WebUserSession["user"] | null {
         candidate.enterpriseBalance ??
         candidate.enterprise_balance,
     ),
+    maxConcurrency: toNumber(candidate.maxConcurrency ?? candidate.max_concurrency),
     activePackages: toActivePackages(candidate.activePackages ?? candidate.active_packages),
   };
 }