[WIP] Enhancement: Inject dependencies into User view helpers

This PR injects dependencies into `User` view helpers by leveraging factories.
Actually, I'm not convinced using aliases.

I've seen a lot of code like this:

```
<?php

use Foo\Entity\Slide as SlideEntity;
use Foo\Entity\User as UserEntity;
// . . .

/* @var CarEntity $car */
/* @var UserEntity $user */
```

and it hasn't really added much clarity when

```
use Foo\Entity;

/* @var Entity\Car $car */
/* @var Entity\User $user */
```

suffices.