fix: Cast userId to string in OpenAI SDK listener handler

Author: mwbrooks

openai-agents-sdk/listeners/events/message.js

@@ -60,7 +60,7 @@ export async function handleMessage({ client, context, event, logger, say, saySt
 
     // For issue submissions the bot posted the message, so the real
     // user_id comes from the metadata rather than the event context.
-    const userId = issueMetadata ? issueMetadata.event_payload.user_id : context.userId;
+    const userId = issueMetadata ? issueMetadata.event_payload.user_id : /** @type {string} */ (context.userId);
 
     // Get conversation history
     const history = conversationStore.getHistory(channelId, threadTs);