[AIP-94] airflowctl command migration

### Body **Goal:** move every *remote* `airflow` CLI command (anything backed by a public REST API endpoint) into `airflowctl`. Admin commands have no API and are local-only. They run components (scheduler, api-server, triggerer, dag-processor, kerberos, standalone), manage the DB, or reach internals directly (DAG parsing/rendering, local provider manager). Those remain in the `airflow` CLI and are out of scope here. **Why:** [AIP-81: Enhanced Security in CLI via Integration of API](https://cwiki.apache.org/confluence/display/AIRFLOW/AIP-81+Enhanced+Security+in+CLI+via+Integration+of+API) and its sub-proposal [AIP-94: Decouple Remote Commands from the airflow CLI](https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=382175838). **Status: converted**. The only work per command now is to add the marker decorator to the listed commands so they are frozen for development. There is no airflowctl migration to do. What to do: - Add the marker decorator to each command on the list. See PR #68726 for how the decorator is converted to a maintainer and developer facing marker (it replaces the user facing deprecation warning). Apply that same decorator to each command. - The decorator is maintainer and developer facing only. It records the airflowctl equivalent and adds a note in the code, and it does not print anything to users or change behavior. - The point of the marker is to freeze these commands for development. Once a command is marked, no new features or behavior changes should land on it. **Admin (no API, local-only, not migrated, stay in the `airflow` CLI):** - `dags`: `show`, `show-dependencies`, `test`, `reserialize` (parse/render DAGs directly) - `tasks`: `test`, `render` (execute/render DAG files directly) - `providers`: `links`, `widgets`, `hooks`, `triggers`, `behaviours`, `logging`, `secrets`, `executors`, `queues`, `notifications`, `configs`, `lazy-loaded`, `auth-managers` (read the local provider manager) ## dags - [x] `dags trigger`…