Release `TestRun` version `v1beta1`

[yorugac]

Feature Description

The TestRun CRD is the first / oldest CRD of the k6-operator (it was initially called K6) and can be considered pretty stable for most cases.

At the moment of writing, TestRun's track record looks like this:

• The rate of new feature additions to TestRun CRD has fallen down recently, though it has not fully stopped.
  • The very last addition happened in June 2025, for the native sidecars support. But the second to last addition happened all the way in July 2024, for the read-only option in volumes.
  • IOW, the rate of additions has pettered out to approx. once per year.
• There are a few breaking changes that will likely happen to the TestRun in foreseeable future:
  • Removal of old-style Istio support, issue.
  • Removal of the starter Pod, issue.
• Another breaking issue is removal of the initializer Pod, issue. But it'll likely take more time to get to it. Ideal solution for it would require some level of support from k6, e.g. like Native Distributed execution or something k6 configuration related.

Suggested Solution (optional)

Given the above, it makes sense to release TestRun CRD as v1beta1 after, for example, resolving the 2 breaking issues mentioned above, and flag v1alpha1 for deprecation. The conversion hook is not necessary in this case, as fundamental structure of the TestRun is not going to change.

Feedback from community is welcome! If there are any strong pros or cons for it, please share in the comments.

Already existing or connected issues / PRs (optional)

No response

[yorugac]

It might be a good idea to do this breaking issue for the TestRun CRD prior to v1beta1 as well: https://github.com/grafana/k6-operator/issues/455