### Description

Add DagProcessor status including latest heartbeat to health endpoint similar to Triggerer status added recently. Related PRs.

https://github.com/apache/airflow/pull/31529
https://github.com/apache/airflow/pull/27755

### Use case/motivation

It helps in dag processor monitoring 

### Related issues

_No response_

### Are you willing to submit a 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)

#
#
from __future__ import annotations
from typing import Any
from airflow.jobs.scheduler_job_runner import SchedulerJobRunner
from airflow.jobs.triggerer_job_runner import TriggererJobRunner
HEALTHY = "healthy"
UNHEALTHY = "unhealthy"
def get_airflow_health() -> dict[str, Any]:
    """Get the health for Airflow metadatabase, scheduler and triggerer."""
    metadatabase_status = HEALTHY
    latest_scheduler_heartbeat = None
    latest_triggerer_heartbeat = None
    scheduler_status = UNHEALTHY
    triggerer_status: str | None = UNHEALTHY
    try: