fix(kumactl): change mtls backend builtin to provided and skipvalidation

[lukidzi]

Motivation

When a user exports a mesh with the mTLS type set to builtin, it is exported as is. However, this is incorrect when the user attempts to import it.

During import, this mesh should be treated as provided since the secrets are already included. Additionally, applying a builtin mesh triggers the generation of new secrets, even though existing ones are already available.

Implementation information

Simplified the logic for better readability:

• Ordered resources: Mesh → Secrets → ... → GlobalSecrets
• Changed mesh from builtin to provided and added skipValidate to ensure Secret creation can happen after the mesh.
• Enabled federation test.
• Fixed Kubernetes export, as skipCreatingInitialPolicies was not being set for the mesh.

Supporting documentation

Fix #13109
Fix: #13217

[github-actions]

Reviewer Checklist

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If something doesn't apply please check the box and add a justification if the reason is non obvious.

• Is the PR title satisfactory? Is this part of a larger feature and should be grouped using > Changelog?
• PR description is clear and complete. It Links to relevant issue as well as docs and UI issues
• This will not break child repos: it doesn't hardcode values (.e.g "kumahq" as an image registry)
• IPv6 is taken into account (.e.g: no string concatenation of host port)
• Tests (Unit test, E2E tests, manual test on universal and k8s)
  • Don't forget ci/ labels to run additional/fewer tests
• Does this contain a change that needs to be notified to users? In this case, UPGRADE.md should be updated.
• Does it need to be backported according to the backporting policy? (this GH action will add "backport" label based on these file globs, if you want to prevent it from adding the "backport" label use no-backport-autolabel label)