💡 Tracking progress

## Feature request
It would be useful to add tracking to next buttons to record tracking progress.

#### What problem does this feature solve?
To know what part the user have already read/studied/learnt

#### What does the proposed API look like?
ExperienceAPI solves this problem: See here:
https://www.ispring.es/blog/xapi-tin-can

#### How should this be implemented in your opinion?
https://www.adaptlearning.org/index.php/get-started/
Above opensource project solves the issue, but looks too heavy for something just documentation oriented.

#### Are you willing to work on this yourself?
I don't know enough the lang to be able to help.

L’issue ne fournit aucun fichier, test ni point d’entrée pour commencer. Commencez par clarifier le modèle de tracking et l’API, puis identifiez le code qui gère les boutons suivant et définissez comment la progression de lecture est enregistrée et vérifiée.

Rédigé par le modèle d'indexation à partir du texte de l'issue.