Add airflowctl tasks failed-deps command

[FrankYang0529]

• Add command airflowctl tasks failed-deps <dag_id> <task_id> <logical_date_or_run_id> [--map-index N].
• TaskInstancesOperations with get and get_dependencies, auto-generating airflowctl taskinstances get / airflowctl taskinstances get-dependencies
• Mark the core CLI command with @deprecated_for_airflowctl("airflowctl tasks failed-deps") and register it in test_command_deprecations.py.
• Extract get_dag_run_by_run_id_or_logical_date to ctl/utils/dag_run.py (shared with dags state).

• related: [AIP-94] airflowctl command migration #68402

---

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

• Yes - Claude Code

---

• 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.
• For significant user-facing changes create newsfragment: {pr_number}.significant.rst, in airflow-core/newsfragments. You can add this file in a follow-up commit after the PR is created so you know the PR number.