Support Gradle configuration cache

[Goooler]

I can repro this in Spotless with ./gradlew equoIde.

* What went wrong:
Configuration cache problems found in this build.

1 problem was found storing the configuration cache.
- Task `:equoIde` of type `dev.equo.ide.gradle.EquoIdeTask`: value '[dev.equo.ide.IdeHookBranding@70c95877, dev.equo.ide.IdeHookWelcome@6934acee, dev.equo.ide.IdeHookBuildship@42dbe544]' is not assignable to 'dev.equo.ide.IdeHook$List'

And a flaky one:

1 problem was found storing the configuration cache.
- Plugin 'dev.equo.ide': external process started 'uname -a'
  See https://docs.gradle.org/8.5/userguide/configuration_cache.html#config_cache:requirements:external_processes

https://docs.gradle.org/current/userguide/configuration_cache.html