Automatically update website in CI & open-source it

At the moment, it seems that @matryer has to manually build and publish a new version of the https://xbarapp.com website.
This means that the maintainer has to do a lot of manual work, and often the website becomes stale (for example, last time the plugin list was updated was in July!).


The website also lacks basic features like proper styling for the category browser, fuzzy search etc.

I think the website should be open-sourced and integrated with some CI like Github Actions.

Start by locating the current website source and the manual build and publish process; the issue names no files or tests. Define the website scope, including whether styling and fuzzy search are included, then determine what open-sourcing it and automated GitHub Actions publishing would require. Done should mean the website can be maintained and published without the maintainer’s manual build step.

Written by the indexing model from the issue text.