Following the recent changes to the API limits, and to better accommodate T420295, the Pageviews Analysis backend could really use a facelift.

Long term, I'd still rather do T378549 as a MediaWiki extension. For now however, I'd like to at least get the repo in a more maintainable state, with a dependable backend, without having to rewrite all of the JS.

Goals

• Same exact user-facing experience, except much faster, in particular for mass-querying tools like Massviews.
• Migrate to Symfony 7.4+
• Use AssetMapper, removing the NPM build step.
• Create Docker container
• Move repo to Gerrit
• Attempt to broaden maintainer base and interested contributors