add null check for eventHook (#1534)

* add null check for eventHook

* move guard to superclass, remove logging that adds no value

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Co-authored-by: rhonda hollis <rhonda@jambonz.org>
Co-authored-by: Dave Horton <daveh@beachdognet.com>

lib/tasks/llm/index.js

@@ -105,6 +105,7 @@ class TaskLlm extends Task {
   }
 
   async sendEventHook(data) {
+    if (!this.eventHook) return;
     await this.cs?.requestor.request('llm:event', this.eventHook, data);
   }