update changelog

Author: Trivo25

CHANGELOG.md

@@ -22,6 +22,13 @@ This project adheres to
 
 - Add `KimchiProof.toJSON()` and `KimchiProof.fromJSON()`
   https://github.com/o1-labs/o1js/pull/2594
+- Add `KimchiVerificationKey.toString()` and
+  `KimchiVerificationKey.fromString()` https://github.com/o1-labs/o1js/pull/2594
+
+### Internal
+
+- Change cache harness to only allow writes when `dump` mode is active.
+  https://github.com/o1-labs/o1js/pull/2599
 
 ## [2.10.0](https://github.com/o1-labs/o1js/compare/114acff...3453d1e53) - 2025-09-27