CHANGELOG: update 3.6 changelog with DowngradeInfo

Signed-off-by: Wei Fu <[email protected]>

CHANGELOG/CHANGELOG-3.6.md

@@ -8,7 +8,7 @@ Previous change logs can be found at [CHANGELOG-3.5](https://github.com/etcd-io/
 
 <hr>
 
-## v3.6.0-rc.0 (2025-02-13)
+## v3.6.0-rc.1 (TBD)
 
 See [code changes](https://github.com/etcd-io/etcd/compare/v3.5.0...v3.6.0).
 
@@ -85,6 +85,7 @@ See [code changes](https://github.com/etcd-io/etcd/compare/v3.5.0...v3.6.0).
 - Add [feature gate `SetMemberLocalAddr`](https://github.com/etcd-io/etcd/pull/19413) to [enable using the first specified and non-loopback local address from initial-advertise-peer-urls as the local address when communicating with a peer]((https://github.com/etcd-io/etcd/pull/17661))
 - Add [Support multiple values for allowed client and peer TLS identities](https://github.com/etcd-io/etcd/pull/18015)
 - Add [`embed.Config.GRPCAdditionalServerOptions`](https://github.com/etcd-io/etcd/pull/14066) to support updating the default internal gRPC configuration for embedded use cases.
+- Add [`DowngradeInfo` to endpoint status response](https://github.com/etcd-io/etcd/pull/19471)
 
 ### etcd grpc-proxy