Moving concurrent-search out of sandbox plugin to core behind feature…

… flag (#7203) (#7408)

(cherry picked from commit fde8fa4)

Signed-off-by: Sorabh Hamirwasia <sohami.apache@gmail.com>
Signed-off-by: Kunal Kotwani <kkotwani@amazon.com>
Co-authored-by: Sorabh <sohami.apache@gmail.com>

CHANGELOG.md

@@ -5,9 +5,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased 2.x]
 ### Added
-- [Extensions] Moving Extensions APIs to support cross versions via protobuf. ([#6960](https://github.com/opensearch-project/OpenSearch/pull/6960))
+- [Extensions] Moving Extensions APIs to support cross versions via protobuf. ([#7402](https://github.com/opensearch-project/OpenSearch/issues/7402))
+- [Extensions] Add IdentityPlugin into core to support Extension identities ([#7246](https://github.com/opensearch-project/OpenSearch/pull/7246))
 - Add connectToNodeAsExtension in TransportService ([#6866](https://github.com/opensearch-project/OpenSearch/pull/6866))
-- [Extensions] Add IdentityPlugin into core to support Extension identities ([#7393](https://github.com/opensearch-project/OpenSearch/pull/7393))
+- Add descending order search optimization through reverse segment read. ([#7244](https://github.com/opensearch-project/OpenSearch/pull/7244))
 
 ### Dependencies
 - Bump `com.netflix.nebula:gradle-info-plugin` from 12.0.0 to 12.1.0
@@ -22,6 +23,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Bump `org.apache.shiro:shiro-core` from 1.9.1 to 1.11.0 ([#7397](https://github.com/opensearch-project/OpenSearch/pull/7397)
 
 ### Changed
+- Enable `./gradlew build` on MacOS by disabling bcw tests ([#7303](https://github.com/opensearch-project/OpenSearch/pull/7303))
+- Moved concurrent-search from sandbox plugin to server module behind feature flag ([#7203](https://github.com/opensearch-project/OpenSearch/pull/7203))
 
 ### Deprecated
 
@@ -32,4 +35,5 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ### Security
 
-
+[Unreleased 3.0]: https://github.com/opensearch-project/OpenSearch/compare/2.x...HEAD
+[Unreleased 2.x]: https://github.com/opensearch-project/OpenSearch/compare/2.5...2.x