[AIP-94] Mark dags clear as migrated to airflowctl

[yuseok89]

related: #68402

Marks airflow dags clear as migrated to its airflowctl equivalent (dags clear, added in #68706) by adding the deprecated_for_airflowctl marker.

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Was generative AI tooling used to co-author this PR?

• Yes (please specify the tool below)
  • Claude Code (Opus 5.5)

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• Read the Pull Request Guidelines for more information. Note: commit author/co-author name and email in commits become permanently public when merged.
• For fundamental code changes, an Airflow Improvement Proposal (AIP) is needed.
• When adding dependency, check compliance with the ASF 3rd Party License Policy.
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[henry3260]

Thanks!

[github-actions]

Backport failed to create: airflow-ctl/v0-1-test. View the failure log Run details

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

In matter of doubt please ask in #release-management Slack channel.

Status	Branch	Result
❌	airflow-ctl/v0-1-test

You can attempt to backport this manually by running:

cherry_picker 4cab3cf airflow-ctl/v0-1-test

This should apply the commit to the airflow-ctl/v0-1-test branch and leave the commit in conflict state marking
the files that need manual conflict resolution.

After you have resolved the conflicts, you can continue the backport process by running:

cherry_picker --continue

If you don't have cherry-picker installed, see the installation guide.