🌱 Enable nobools linter

[moko-poi]

What type of PR is this?

/kind cleanup
/kind support

What this PR does / why we need it:

Enables the nobools linter in golangci-kal and adds targeted //nolint:kubeapilinter exemptions for existing boolean API fields and test struct fields.
This keeps the API surface and behavior fully backward compatible while allowing the stricter linter to be enforced for newly added fields going forward.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #5489

Special notes for your reviewer:

• The linter is enabled globally, but all changes to code are limited to adding //nolint:kubeapilinter // nobools: Existing API field, not changing to preserve backwards compatibility. comments on existing fields.
• No API types or JSON schemas are changed; this should be a no-op for generated CRDs and existing clusters.
• Please double-check that all boolean API fields that would violate nobools are either:
  • existing and explicitly annotated with //nolint, or
  • newly added and intentionally left as-is (in which case they should be reconsidered as enums).

Checklist:

• squashed commits
• includes documentation
• includes emoji in title
• adds unit tests
• adds or updates e2e tests

Release note:

Enable the `nobools` kubeapilinter rule and add explicit exemptions for existing boolean API fields to preserve backward compatibility.

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @moko-poi. Thanks for your PR.

I'm waiting for a github.com member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[AndiDog]

/ok-to-test

[k8s-ci-robot]

@moko-poi: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-cluster-api-provider-aws-test	b926621	link	true	/test pull-cluster-api-provider-aws-test

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.