Add a changelog entry for PR #3068

PR #3068: Use Tune IQ for layered image inter-frame encoding

CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a6894aa..51ce939 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,7 @@
 
 * Require C11 for compilation. Public headers will remain C99.
 * Add --jobs flag to avifgainmaputil and enable auto tiling.
+* Use AOM_TUNE_IQ for layered image inter-frame encoding.
 
 ## [1.4.1] - 2026-03-20