### Description

https://github.com/apache/airflow/pull/17946 implements a `/robots.txt` endpoint to block search engines crawling Airflow - in the cases where it is (accidentally) exposed to the public Internet.

If we record any GET requests to that end-point we'd have a strong warning flag that the deployment is exposed, and could issue a warning in the UI, or even enable some kill-switch on the deployment. 

Some deployments are likely intentionally available and rely on auth mechanisms on the `login` endpoint, so there should be a config option to suppress the warnings.

An alternative approach would be to monitor for requests from specific user-agents used by crawlers for the same reasons

### Use case/motivation

People who accidentally expose airflow have a slightly higher chance of realising they've done so and tighten their security.

### Related issues

_No response_

### Are you willing to submit a PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

airflow/www/views.py
'state',
        'dag_id',
        'execution_date',
        'run_id',
        'run_type',
        'start_date',
        'end_date',
        'external_trigger',
    ]
    label_columns = {
        'execution_date': 'Logical Date',
    }
    edit_columns = ['state', 'dag_id', 'execution_date', 'start_date', 'end_date', 'run_id', 'conf']
    
    order_columns = [
        'state',
        'dag_id',
        'execution_date',
        'run_id',
        'run_type',
        'queued_at',
        'start_date',
        'end_date',
        'external_trigger',
        'conf',
    ]
    base_order = ('execution_date', 'desc')
    base_filters = [['dag_id', DagEditFilter, lambda: []]]
    edit_form = DagRunEditForm
    def duration_f(self):