### What do you see as an issue?

The documentation for zombie tasks https://airflow.apache.org/docs/apache-airflow/stable/core-concepts/tasks.html#zombie-undead-tasks is a bit abstract at the moment. There is a scope for enhancing the document by explaining how Airflow detects tasks as zombies

### Solving the problem

We can enhance the documentation by translating this query https://github.com/astronomer/airflow/blob/main/airflow/jobs/scheduler_job_runner.py#L1721 to a layman readable text in our documentation.

### Anything else

It might also help to add developer contribution steps to reproduce zombies locally.

### Are you willing to submit 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)

self.processor_agent.end()
                except Exception:
                    self.log.exception("Exception when executing DagFileProcessorAgent.end")
            self.log.info("Exited execute loop")
        return None
    @provide_session
    def _update_dag_run_state_for_paused_dags(self, session: Session = NEW_SESSION) -> None:
        try:
            paused_runs = session.scalars(
                select(DagRun)
                .join(DagRun.dag_model)
                .join(TI)
                .where(
                    DagModel.is_paused == expression.true(),
                    DagRun.state == DagRunState.RUNNING,
                    DagRun.run_type != DagRunType.BACKFILL_JOB,
                )
                .having(DagRun.last_scheduling_decision <= func.max(TI.updated_at))
                .group_by(DagRun)
            )
            for dag_run in paused_runs:
                dag = self.dagbag.get_dag(dag_run.dag_id, session=session)
                if dag is not None:
                    dag_run.dag = dag
                    _, callback_to_run = dag_run.update_state(execute_callbacks=False, session=session)
                    if callback_to_run:
                        self._send_dag_callbacks_to_processor(dag, callback_to_run)
        except Exception as e:  
            self.log.exception("Failed to update dag run state for paused dags due to %s", e)
    def _run_scheduler_loop(self) -> None: