Add identity verification alert to pipeline editor

What does this MR do and why?

Adds an alert to the pipeline editor for users who are required to complete identity verification before running their first pipeline, so the requirement is communicated before they commit changes.

• Alert title: Verify your identity to commit this change
• Message: This step is separate from the verification you completed during registration.
• Button: Verify identity (default variant, opens in a new tab, sticky)

Also updates the existing alert on the failed pipeline detail page to use the same copy and a confirm-variant button, matching the design.

References

Closes #588870

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Enable identity verification requirements for CI in the Rails console:

   ApplicationSetting.current.update!(ci_requires_identity_verification_on_free_plan: true)

2. As a user who has not completed identity verification, visit a project's pipeline editor: http://127.0.0.1:3000/<namespace>/<project>/-/ci/editor

3. Confirm the verification alert renders above the commit form with the expected copy and a default-variant "Verify identity" button that opens /-/identity_verification in a new tab.

4. Commit a pipeline change and let the pipeline fail due to unverified identity; visit the pipeline's detail page and confirm the alert there uses a confirm-variant button.

MR acceptance checklist

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