### Summary

The [list of builtin modules](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/index.html) shows two modules with similar names and identical descriptions:

> [systemd module](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/systemd_module.html#ansible-collections-ansible-builtin-systemd-module) – Manage systemd units
> [systemd_service module](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/systemd_service_module.html#ansible-collections-ansible-builtin-systemd-service-module) – Manage systemd units

My guess was that `systemd_service` would manage services running with systemd, and `systemd` would manage `systemd` itself. But the description is identical. The synopsis is identical. The arguments and examples appear identical.

As a user, I expect that if one module has two names, the documentation would state that one is an alias.

Looking at [the code](https://github.com/ansible/ansible/blob/devel/lib/ansible/modules/systemd.py) I see that `systemd` is symlinked to `systemd_service.py`.

Please modify the documentation to state that one is an alias of the other, and they are identical.


### Issue Type

Documentation Report

### Component Name

systemd_service

### Ansible Version

```console
N/A
```


### Configuration

```console
N/A
```


### OS / Environment

N/A

### Additional Information

For context, my objective is to create a service file, and then enable+start it. I was hoping that there would be one module to do that. But then I saw there are two similar ones, and I thought one would create the .service file, and the other would load+run it. But that doesn't appear to be the case either.

### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
- Whether the unit should start on boot. B(At least one of state and enabled are required.)
        type: bool
    force:
        description:
            - Whether to override existing symlinks.
        type: bool
        version_added: 2.6
    masked:
        description:
            - Whether the unit should be masked or not, a masked unit is impossible to start.
        type: bool
    daemon_reload:
        description:
            - Run daemon-reload before doing any other operations, to make sure systemd has read any changes.
            - When set to V(true), runs daemon-reload even if the module does not start or stop anything.
        type: bool
        default: no
        aliases: [ daemon-reload ]
    daemon_reexec:
        description:
            - Run daemon_reexec command before doing any other operations, the systemd manager will serialize the manager state.
        type: bool
        default: no
        aliases: [ daemon-reexec ]
        version_added: "2.8"
    scope:
        description:
            - Run systemctl within a given service manager scope, either as the default system scope V(system),
              the current user's scope V(user), or the scope of all users V(global).
            - "For systemd to work with 'user', the executing user must have its own instance of dbus started and accessible (systemd requirement)."