### Describe the issue with documentation

`BaseOperator` type hints for `retry_delay` and `max_retry_delay` shows `timedelta` only, however the params also accept `float` seconds values.
Also, type hint for `dag` param is missing.
More precise type hints and params descriptions in the docs can help to understand the code behavior easier.

### How to solve the problem

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [X] 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/models/baseoperator.py
self,
        upstream: bool = False,
        found_descendants: Optional[Set[str]] = None,
    ) -> Set[str]:
        """Get a flat set of relatives' ids, either upstream or downstream."""
        if not self._dag:
            return set()
        if not found_descendants:
            found_descendants = set()
        relative_ids = self.get_direct_relative_ids(upstream)
        for relative_id in relative_ids:
            if relative_id not in found_descendants:
                found_descendants.add(relative_id)
                relative_task = self._dag.task_dict[relative_id]
                relative_task.get_flat_relative_ids(upstream, found_descendants)
        return found_descendants
    def get_flat_relatives(self, upstream: bool = False):
        """Get a flat list of relatives, either upstream or downstream."""
        if not self._dag:
            return set()
        from airflow.models.dag import DAG
        dag: DAG = self._dag
        return list(map(lambda task_id: dag.task_dict[task_id], self.get_flat_relative_ids(upstream)))
    @provide_session
    def run(