Update CHANGELOG

Author: popescu-v

CHANGELOG.md

@@ -6,6 +6,12 @@
   - Example: 10.2.1.4 is the 5th version that supports khiops 10.2.1.
 - Internals: Changes in *Internals* sections are unlikely to be of interest for data scientists.
 
+## Unreleased -
+
+### Added
+- (`core`) Dictionary API support for dictionary, variable and variable block
+  comments, and dictionary and variable block internal comments.
+
 ## 11.0.0.0-b.0 - 2025-07-10
 
 ### Added