Update NEWS

Author: mfkl

NEWS

@@ -4,6 +4,14 @@ This document will focus on the release notes of vlc-unity itself, unless specif
 For LibVLC changes, head over to https://code.videolan.org/videolan/vlc/-/blob/master/NEWS and the git history.
 For LibVLCSharp changes, see https://code.videolan.org/videolan/LibVLCSharp/-/blob/master/NEWS.
 
+2025-4 (All platforms)
+- scene: add missing null checks
+- Unity: implement VLCAudioSource
+- trial: various watermark fixes
+- iOS: fix build
+- CI: build fixes and improvements
+- libvlc engine update (24/09)
+
 2025-3 (All platforms)
 - 16 bit color depth format support on Windows with new TextureHelper (see Minimal scene for example use)
 - sample scenes: fix texture leaks