### Apache Airflow version

2.5.1

### What happened

Context: I am attempting to use [TypedDict](https://docs.python.org/3/library/typing.html#typing.TypedDict) objects to maintain the keys used in DAG params in a single place, and check for key names across multiple DAGs that use the params.
This raises an error with `mypy` as `params` expects an `Optional[Dict]`. Due to the invariance of `Dict`, this does not accept `TypedDict` objects.

What happened: I passed a `TypedDict` to the `params` arg of `DAG` and got a TypeError.

### What you think should happen instead

`TypedDict` objects should be accepted by `DAG`, which should accept `Optional[Mapping[str, Any]]`. 

Unless I'm mistaken, `params` are converted to a `ParamsDict` class and therefore the appropriate type hint is a generic `Mapping` type.

### How to reproduce

Steps to reproduce

```Python
from typing import TypedDict

from airflow import DAG
from airflow.models import Param

class ParamsTypedDict(TypedDict):
    str_param: Param

params: ParamsTypedDict = {
    "str_param": Param("", type="str")
}

with DAG(
    dag_id="mypy-error-dag",
    # The line below raises a mypy error
    # Argument "params" to "DAG" has incompatible type "ParamsTypedDict"; expected "Optional[Dict[Any, Any]]"  [arg-type]
    params=params,  
) as dag:
    pass
```

### Operating System

Amazon Linux

### Versions of Apache Airflow Providers

_No response_

### Deployment

Docker-Compose

### Deployment details

_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)

return self._dag
    @property  
    def dag(self) -> DAG:  
        """Returns the Operator's DAG if set, otherwise raises an error"""
        if self._dag:
            return self._dag
        else:
            raise AirflowException(f"Operator {self} has not been assigned to a DAG yet")
    @dag.setter
    def dag(self, dag: DAG | None):
        """
        Operators can be assigned to one DAG, one time. Repeat assignments to
        that same DAG are ok.
        """
        from airflow.models.dag import DAG
        if dag is None:
            self._dag = None
            return
        if not isinstance(dag, DAG):
            raise TypeError(f"Expected DAG; received {dag.__class__.__name__}")
        elif self.has_dag() and self.dag is not dag:
            raise AirflowException(f"The DAG assigned to {self} can not be changed.")
        if self.__from_mapped:
            pass  
        elif self.task_id not in dag.task_dict:
            dag.add_task(self)
        elif self.task_id in dag.task_dict and dag.task_dict[self.task_id] is not self:
            dag.add_task(self)
        self._dag = dag
    def has_dag(self):