Separate validation pipelines from the kpt file

[ciaranjohnston]

Describe your problem

Currently validation and mutation pipelines are part of the kptfile. Separating the validation pipelines out into separate files would allow for different rules and different pipelines to execute in different conditions or according to different user preferences / permissions. Git + OWNERS file can enforce rules

• Allow to break the pipeline from the kpfile resource -> @kispaljr
  • Define the pipeline in a separate file
  • This allow us to separate the pipelines like mutation pipeline and validation pipeline
  • Open up the possibility to have different kind of pipelines
  • In the far future we can make the pipelines pluggable, like create other pipelines not implemented in kpt, like Ansible, GitLab or whatever

Enhancement discussed as part of the Nephio meetup Sept 2025