Update kotlinx.serialization to v1.9.0 (#3302)

* Update kotlinx.serialization to v1.9.0

* Update kotlinx-datetime

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Co-authored-by: Christos  Malliaridis <c.malliaridis@gmail.com>

Author: solrbot

gradle/libs.versions.toml

@@ -148,8 +148,8 @@ kotlinx-atomicfu = "0.29.0"
 # @keep for version alignment
 kotlinx-browser = "0.3"
 kotlinx-coroutines = "1.10.1"
-kotlinx-datetime = "0.6.2"
-kotlinx-serialization = "1.8.0"
+kotlinx-datetime = "0.7.1"
+kotlinx-serialization = "1.9.0"
 ktor = "3.2.2"
 langchain4j = "0.35.0"
 # @keep Link checker version used in ref-guide