fix: ignore system messages — agent only responds to humans/agents

src/router.ts

@@ -67,6 +67,12 @@ export class EventRouter {
       return;
     }
 
+    // Don't respond to system messages (task status changes, assignments, etc.)
+    if (authorType === 'system') {
+      this.log.debug('Ignoring system message: %s', content.slice(0, 100));
+      return;
+    }
+
     if (!content) {
       this.log.warn({ data }, 'message.new event missing content');
       return;