Update compiler plugin ID to "dev.drewhamilton.poko" (was previously "poko-compiler-plugin").

Deprecate @SkipSupport annotation and stop requiring it for using @Poko.Skip annotation. Update deprecation level of @ArrayContentSupport and @ArrayContentBased to ERROR.

Compile with Kotlin 2.3.0. Compile with Java 25, except for the Gradle plugin, which is compiled with Java 24.

Drop support for Kotlin 2.2 due to incompatibility. Increase the minimum supported Gradle version to 9.0.0.