chore(schemas): refresh releases and retain newest five versions

[github-actions]

Adds stable upstream Kubernetes and CRD snapshots and retires versions beyond the newest five per product and release track. Retained files are unchanged. New snapshots include source provenance and SHA-256 checksums; retired documentation URLs age out. The newest imported Kubernetes version becomes the default automatically.

The update workflow validated the complete corpus, rendered documentation, ran Go and frontend tests, and smoke-tested the production container and browser interactions before opening this PR.

Review the schema changes and approve any approval-required GitHub Actions runs before merging. This PR is not automatically merged or deployed; production promotion remains through Spacelift.

[infracost]

💰 Infracost report

This pull request is aligned with your company's FinOps policies and the Well-Architected Framework.

Monthly estimate increased by $0 📈

Estimate details (includes details of unsupported resources)

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2 projects have no cost estimate changes.
Run the following command to see their breakdown: infracost breakdown --path=/path/to/code

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22 cloud resources were detected:
∙ 17 were estimated
∙ 4 were free
∙ 1 is not supported yet, see https://infracost.io/requested-resources:
  ∙ 1 x google_cloud_run_v2_service_iam_member

_{This comment will be updated when code changes.}