Add changelog entries for changes

Author: rblenkinsopp

Packages/Tracking/CHANGELOG.md

@@ -6,6 +6,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 [docs-website]: https://docs.ultraleap.com/unity-api/ "Ultraleap Docs"
 
+## [Next]
+
+### Fixed
+- Fixed a file descriptor leak in `Connection` that exhausted the Unity process's OS handle limit after repeated play-mode start/stop cycles.
+- Fixed an unmanaged memory leak where the marshalled server namespace string passed to LeapC was not freed.
+- Fixed a managed memory leak in `Controller` where event subscriptions on the pooled `Connection` were not removed on disposal.
+- Fixed a missing timeout on `Connection` shutdown which could lead to delays in applications exiting.
+
 ## [7.3.0] - 25/02/2026
 
 ### Added