### Apache Airflow version

main (development)

### What happened

Currently when a new task is added to a dag and in the grid view, a user selects the top level of a dag run and then clicks on "Queue up new tasks", the list returned by the confirmation box is always empty. 

It appears that where the list of tasks is expected to be set, [here](https://github.com/apache/airflow/blob/ada91b686508218752fee176d29d63334364a7f2/airflow/api/common/mark_tasks.py#L516), `res` will always be an empty list. 


### What you think should happen instead

The UI should return a list of tasks that will be queued up once the confirmation button is pressed. 

### How to reproduce

Create a dag, trigger the dag, allow it to complete. 

Add a new task to the dag, click on "Queue up new tasks", the list will be empty.

### Operating System

n/a

### Versions of Apache Airflow Providers

2.3.3 and upwards including main. I've not looked at earlier releases. 

### Deployment

Other 3rd-party Helm chart

### Deployment details

_No response_

### Anything else

I have a PR prepared for this issue. 

### 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)

from sqlalchemy.orm import Session, joinedload
from wtforms import SelectField, validators
from wtforms.validators import InputRequired
import airflow
from airflow import models, plugins_manager, settings
from airflow.api.common.mark_tasks import (
    set_dag_run_state_to_failed,
    set_dag_run_state_to_queued,
    set_dag_run_state_to_success,
    set_state,
)
from airflow.compat.functools import cached_property
from airflow.configuration import AIRFLOW_CONFIG, conf
from airflow.datasets import Dataset
from airflow.exceptions import AirflowException, ParamValidationError, RemovedInAirflow3Warning
from airflow.executors.executor_loader import ExecutorLoader
from airflow.jobs.base_job import BaseJob
from airflow.jobs.scheduler_job import SchedulerJob
from airflow.jobs.triggerer_job import TriggererJob
from airflow.models import Connection, DagModel, DagTag, Log, SlaMiss, TaskFail, XCom, errors
from airflow.models.abstractoperator import AbstractOperator
from airflow.models.dag import DAG, get_dataset_triggered_next_run_info
from airflow.models.dagcode import DagCode
from airflow.models.dagrun import DagRun, DagRunType
from airflow.models.dataset import DagScheduleDatasetReference, DatasetDagRunQueue, DatasetEvent, DatasetModel
from airflow.models.mappedoperator import MappedOperator
from airflow.models.operator import Operator
from airflow.models.serialized_dag import SerializedDagModel
from airflow.models.taskinstance import TaskInstance, TaskInstanceNote
from airflow.providers_manager import ProvidersManager