### 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
"""Base View to set Airflow related properties"""
    from airflow import macros
    route_base = ''
    extra_args = {
        
        'macros': macros,
        'get_docs_url': get_docs_url,
    }
    if not conf.getboolean('core', 'unit_test_mode'):
        extra_args['sqlite_warning'] = settings.engine.dialect.name == 'sqlite'
        extra_args['sequential_executor_warning'] = conf.get('core', 'executor') == 'SequentialExecutor'
    line_chart_attr = {
        'legend.maxKeyLength': 200,
    }
    def render_template(self, *args, **kwargs):
        
        if TriggererJob.is_needed():
            kwargs["triggerer_job"] = lazy_object_proxy.Proxy(TriggererJob.most_recent_job)
        return super().render_template(
            *args,
            
            scheduler_job=lazy_object_proxy.Proxy(SchedulerJob.most_recent_job),
            **kwargs,
        )
def add_user_permissions_to_dag(sender, template, context, **extra):