Embedded Cluster 2.9.0 release notes (#3457)

* Embedded Cluster 2.9.0 release notes

* Update rn-embedded-cluster.md

* fix headings

---------

Co-authored-by: Alex Parker <[email protected]>
Co-authored-by: Paige Calvert <[email protected]>

Author: 3 people

docs/release-notes/rn-embedded-cluster.md

@@ -12,6 +12,35 @@ Additionally, these release notes list the versions of Kubernetes and Replicated
 
 <!--RELEASE_NOTES_PLACEHOLDER-->
 
+## 2.9.0
+
+Released on August 18, 2025
+
+<table>
+  <tr>
+    <th>Version</th>
+    <td id="center">2.9.0+k8s-1.32</td>
+    <td id="center">2.9.0+k8s-1.31</td>
+    <td id="center">2.9.0+k8s-1.30</td>
+  </tr>
+  <tr>
+    <th>Kubernetes Version</th>
+    <td id="center">1.32.7</td>
+    <td id="center">1.31.11</td>
+    <td id="center">1.30.14</td>
+  </tr>
+  <tr>
+    <th>KOTS Version</th>
+    <td id="center" colspan="3">1.125.2</td>
+  </tr>
+</table>
+
+### New Features {#new-features-2-9-0}
+* Adds support for Kubernetes 1.32.
+
+### Bug Fixes {#bug-fixes-2-9-0}
+* Fixes an issue where the `--network-interface` flag wasn't respected when joining a node.
+
 ## 2.8.1
 
 Released on August 6, 2025