[build] add checks to ensure that no modules which are part of the IDE plugin do not use experimental stdlib API

to ensure binary compatibility with stdlib inside IntelliJ.

This includes using the latest stable kotlin API version and
forbidding using experimental declarations from stdlib.

^KT-62510

gradle.properties

@@ -29,6 +29,10 @@ cacheRedirectorEnabled=true
 defaultSnapshotVersion=2.0.255-SNAPSHOT
 kotlinLanguageVersion=2.0
 
+# Should be less or equal to the Kotlin stdlib version used inside IntelliJ IDEA repository, see KT-62510.
+# IntelliJ IDEA Kotlin stdlib version can be found at https://github.com/JetBrains/intellij-community/blob/master/.idea/libraries/kotlin_stdlib.xml
+kotlinApiVersionForProjectsUsedInIntelliJKotlinPlugin=1.9
+
 kotlin.build.gradlePlugin.version=0.0.40
 
 #maven.repository.mirror=http://repository.jetbrains.com/remote-repos/