Frontend rewrite

[art-w]

The frontend works well, but it has become hard to maintain in the long run:

• The plotting library limits what we can display, we have to switch to something more flexible
• It's a big hack to share code between the pipeline and the frontend, we can only share a single file with some inlined bits of yojson
• It's hard to display pipeline informations on the frontend, since they can only communicate via postgres on one side and graphql on the other
• And yeah, I'm not happy that Rescript is slowly changing OCaml semantics, is stuck on 4.09, the abysimal build system, etc. and I haven't even mentionned the npm/nodejs monster that creeps under a mountain of code.

The good news is that we don't actually need that much javascript on the frontend! We could just have a standard webserver written in OCaml and push HTML to the browser.

• Only the graphs require javascript, since we have to know their size to draw them properly.
• We could also drop the Hasura/GraphQL. It's cool and all, but it creates another mismatch / redundancy between the existing SQL code in the pipeline and the frontend.

[punchagan]

The good news is that we don't actually that much javascript on the frontend! We could just have a standard webserver written in OCaml and push HTML to the browser.

We've a lot of Rescript right now, though!