Update to Kotlin 2.3.0

[Jolanrensen]

https://kotlinlang.org/docs/whatsnew23.html

• Update .toml and subprojects
• Also, update all examples
• Update docs
• Instant should now be stable too!
• Finish (Nested) typealias KDocs #1543 now nested type aliases are stable

[Jolanrensen]

One small thing; we cannot bump KSP because of #1445 and we potentially plan on removing KSP anyway (well, the gradle plugin)

[Jolanrensen]

Blocked by https://youtrack.jetbrains.com/issue/KT-83292/Nothing-KType-not-equal-to-other-Nothing-KType-in-2.3.0-anymore