fix: resolve worker build errors blocking Docker deploy

- Add OPENROUTER_API_KEY (optional) to env schema so tsc can resolve it
- Add pg + @types/pg to worker deps for outbox-listener
- Explicit Error type on pg client error handler

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/worker/src/outbox/outbox-listener.ts

@@ -93,7 +93,7 @@ export async function startOutboxListener(
       .catch((err: unknown) => logger.error({ err, eventId }, 'Outbox notification handler error'));
   });
 
-  pgClient.on('error', (err) => logger.error({ err }, 'Outbox pg client error'));
+  pgClient.on('error', (err: Error) => logger.error({ err }, 'Outbox pg client error'));
 
   logger.info('Outbox listener ready');
   return pgClient;