add a plugin for hmr to support django templates

[martindemello]

MrBin99/django-vite#17 was closed because it was part of vite.config.js rather than the django plugin. However, the solution will be similar for any django project, so it seems worth adding it to the example project at least.

[GatoVuelta]

Implemented already, include:

{% load django_vite %}
...
{% vite_hmr_client %}