docs: v3.4.2 changelog

Author: kozistr

docs/changelogs/v3.4.2.md

@@ -5,10 +5,20 @@
 * Implement `SCION` optimizer. (#348, #352)
     * [Training Deep Learning Models with Norm-Constrained LMOs](https://arxiv.org/abs/2502.07529)
 
+### Update
+
+* Update ScheduleFreeSGD, AdamW, RAdam optimizers with the latest. (#351, #353)
+* Remove `use_palm` variant in ScheduleFree optimizer due to instability. (#353)
+* Ranger25 optimizer. (#353)
+
+### Fix
+
+* Remove `weight decouple` parameter in ScheduleFree optimizers. (#351, #353)
+
 ### Docs
 
 * Fix `AliG` optimizer visualization. (#350)
 
 ### Contributions
 
-thanks to @AidinHamedi
+thanks to @AidinHamedi, @hatonosuke