fix(Pinecone Vector Store Node): Fix vector store nodes execution iss…

…ue (#8968)

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>

packages/@n8n/nodes-langchain/utils/helpers.ts

@@ -22,7 +22,7 @@ export function getMetadataFiltersValues(
 }
 
 export function isChatInstance(model: unknown): model is BaseChatModel {
-	const namespace = (model as BaseLLM | BaseChatModel).lc_namespace;
+	const namespace = (model as BaseLLM | BaseChatModel)?.lc_namespace ?? [];
 
 	return namespace.includes('chat_models');
 }