Warn users when clearing task in overrun dag

Related to #25440, I think the airflow UI should at least have warning popup/confirmation when a user attempts to clear a task from a dag that has already finished, or more precisely, with the following context: * Warn user that a new dag run will be created if the dag is already finished * If task or dag timeout has been reached, warn user that this will reset the timeout. * If timeout has not been reached, ask user if timeout should be reset or keep to original timeout (warning user how much time will be left). Because at the moment it does not seem clear or obvious to me/users that clearing a task will affect these timeouts, and this can have serious impacts to dags that run daily and depend on the dag timeout to make sure it doesn't overshoot to the next day. _Originally posted by @samvel1024 in https://github.com/apache/airflow/discussions/25440_