feat: change documentation engine

This MR updates the documentation from mkdocs to docusaurus.

Docusaurus is a well know tool for building documentations. Since we are working in javascript environment, docusaurus makes more sense to use because its supports jsx and mdx files. Configuration is also done in typescript with types.

Check out the version https://doc-self-data-rec.apps.grandlyon.com/

Features

• beautiful & more modern design
• button to copy code snippets
• router file base, no more routes.yml
• easier section sharing (by clicking on headers)
• makes admonition easier to write (without having to indent content)
• fast (150ms reload)
• supports dark mode out of the box

Other

This mr also :

• adds useful links to our workspace in the footer

TODO

• implement search engine
• center images
• uppercase folder
• plantuml https://github.com/webgears/remarkable-plantuml
• update home

How to review

Check every page and make sure that everything is all good. you don't have to check all changes.

Some tests files are still present but no referenced like index-tsx in case we want to use this feature. Right now it brings complex changes compared to the md file but we might want to use it later for a better looking page (http://localhost:3001/index-tsx)