[Docs] Generate release notes for 8.15.2 (#193845)

## Summary

This PR adds release notes for the 8.15.2 version.

docs/CHANGELOG.asciidoc

@@ -10,6 +10,7 @@
 
 Review important information about the {kib} 8.x releases.
 
+* <<release-notes-8.15.2>>
 * <<release-notes-8.15.1>>
 * <<release-notes-8.15.0>>
 * <<release-notes-8.14.3>>
@@ -72,6 +73,52 @@ Review important information about the {kib} 8.x releases.
 
 --
 
+[[release-notes-8.15.2]]
+== {kib} 8.15.2
+
+The 8.15.2 release includes the following enhancements and bug fixes.
+
+[float]
+[[enhancement-v8.15.2]]
+=== Enhancements
+Elastic Security solution::
+For the Elastic Security 8.15.2 release information, refer to {security-guide}/release-notes.html[_Elastic Security Solution Release Notes_].
+Fleet::
+* Bumps maximum supported package spec version to 3.2 ({kibana-pull}193574[#193574]).
+Kibana security::
+* Adds a feature to add support for handling `syslogs with unsupported message body` ({kibana-pull}192817[#192817]).
+* Automatic Import now performs reproducible sampling from the list of log entries instead of just truncating them ({kibana-pull}191598[#191598]).
+* Adds support for Google Gemini, OpenAI, and Azure OpenAI connectors to Automatic Import ({kibana-pull}191577[#191577]).
+* Displays better error messages for issues with logs sample file upload in Automatic Import ({kibana-pull}191310[#191310]).
+
+[float]
+[[fixes-v8.15.2]]
+=== Bug fixes
+Alerting::
+* Fixes error when saving a rule after toggling alerts filter properties on and off ({kibana-pull}192522[#192522]).
+Dashboards::
+* Fixes map layers that disappear from map panel when using session storage to continue editing a dashboard ({kibana-pull}193629[#193629]).
+Discover::
+* Fixes "View conflicts" button when a data view ID has special characters ({kibana-pull}192374[#192374]).
+Elastic Observability solution::
+* Fixes OpenTelemetry agent names ({kibana-pull}193134[#193134]).
+* Resolves an issue for multi-step browser journeys where timings for cached resources within the same step were inaccurate within the waterfall chart ({kibana-pull}193089[#193089]).
+* Updates parsing to skip replacing missing values in Synthetics monitors ({kibana-pull}192662[#192662]).
+Elastic Security solution::
+For the Elastic Security 8.15.2 release information, refer to {security-guide}/release-notes.html[_Elastic Security Solution Release Notes_].
+Fleet::
+* Prevents extra agent_status call with empty policyId ({kibana-pull}192549[#192549]).
+* Sets correct title for Restart upgrade agent modal under agent list ({kibana-pull}192536[#192536]).
+Kibana security::
+* Stops removing message field for unstructured logs when using Automatic Import ({kibana-pull}193678[#193678]).
+* Integrations created using Automatic Import now indicate that they have been developed by the `Community` instead of Elastic ({kibana-pull}193002[#193002]).
+* Fixes issues with rendering the package manifest in Automatic Import ({kibana-pull}192316[#192316]).
+Machine Learning::
+* Fixes deletion in Check interval input for anomaly detection rule ({kibana-pull}193420[#193420]).
+* Fixes unnecessary ML services initialization during plugin setup ({kibana-pull}193153[#193153]).
+* Fixes link to anomaly detection wizard from pattern analysis in Discover ({kibana-pull}192375[#192375]).
+* Fixes an issue with the `http_endpoint` input config loading incorrectly in an Automatic Import workflow ({kibana-pull}191964[#191964]).
+
 [[release-notes-8.15.1]]
 == {kib} 8.15.1