Handles undefined message case in message list creation

Prevents potential errors by returning an empty list if the
specified message ID does not exist in the history. This
enhancement ensures robustness in scenarios where a message
ID may be missing, avoiding further processing and potential
exceptions.

src/lib/utils/index.ts

@@ -1225,6 +1225,9 @@ export const createMessagesList = (history, messageId) => {
 	}
 
 	const message = history.messages[messageId];
+	if (message === undefined) {
+		return [];
+	}
 	if (message?.parentId) {
 		return [...createMessagesList(history, message.parentId), message];
 	} else {