docs(event-streaming): add Wazuh integration guide (#734)

* docs(event-streaming): add Wazuh integration guide

Documents how to wire NetBird's Generic HTTP event-streaming integration
to a self-hosted Wazuh manager: NetBird-side configuration, KQL queries
for audit and traffic events in the Wazuh dashboard, and a schema
reference for both event shapes via the receiver wrapper.

Adds the page to the Stream Activity Events sidebar and the
event-streaming index.

* docs(event-streaming): replace Wazuh Generic HTTP screenshot

src/components/NavigationDocs.jsx

@@ -436,6 +436,10 @@ export const docsNavigation = [
                 title: 'Generic HTTP',
                 href: '/manage/activity/event-streaming/generic-http',
               },
+              {
+                title: 'Wazuh',
+                href: '/manage/activity/event-streaming/wazuh',
+              },
             ],
           },
         ],