feat(client): send X-Stainless-Kotlin-Version header

Author: stainless-app[bot]

openlayer-java-core/src/main/kotlin/com/openlayer/api/core/ClientOptions.kt

@@ -404,6 +404,7 @@ private constructor(
             headers.put("X-Stainless-Package-Version", getPackageVersion())
             headers.put("X-Stainless-Runtime", "JRE")
             headers.put("X-Stainless-Runtime-Version", getJavaVersion())
+            headers.put("X-Stainless-Kotlin-Version", KotlinVersion.CURRENT.toString())
             apiKey?.let {
                 if (!it.isEmpty()) {
                     headers.put("Authorization", "Bearer $it")