(kafka_mirrormaker) Update advanced parameters

static/includes/config-kafka_mirrormaker.md

@@ -12,6 +12,12 @@ import Link from '@docusaurus/Link'
         <p className="title">IP filter</p><div className="description"><p>Allow incoming connections from CIDR address block, e.g. '10.20.0.0/16'</p></div>
       </td>
     </tr>
+    <tr>
+      <td>
+        <div className="param"><p className="name"><Link id="preferred_zones"/><Link to="#preferred_zones"><strong>preferred_zones</strong></Link></p><p><code className="type">array,null</code></p></div>
+        <div className="description"><p>List of preferred zone IDs for service node placement. Nodes will be placed in these zones when available. If a specified zone is unavailable (e.g., due to capacity constraints), nodes will be placed in other available zones to maintain the configured number of zones for availability. Invalid zone IDs are rejected at configuration time. Zone IDs are cloud-specific: AWS uses zone IDs like 'euc1-az1', GCP uses zone names like 'europe-west1-a', and Azure uses 'location/zone' format like 'germanywestcentral/1'. If single_zone is enabled with an availability_zone, that setting takes precedence over preferred_zones. Changes take effect on next node recreation (e.g., maintenance or plan change). For eligible plans, nodes outside preferred zones are automatically rebalanced once per day.</p></div>
+      </td>
+    </tr>
     <tr>
       <td>
         <div className="param"><p className="name"><Link id="service_log"/><Link to="#service_log"><strong>service_log</strong></Link></p><p><code className="type">boolean,null</code></p></div>