Frontend: tracing-tree: improve usability

[W95Psp]

The traces are super useful for debugging the frontend.
But they also are quite verbose and hard to browse.

Debugging would be much easier if we had a tool to interactively browse traces.

A cheap way of doing that could be to parse the (tree) traces and reshape them as JSON, so that we can jless them.

jless offers everything we want there: it's super fast, it can search efficiently into data, it's easy to fold the data, etc.

I suspect #686 is not so hard to fix. But currently, debugging is a huge pain because the logs are hard to browse.

[franziskuskiefer]

@W95Psp any updates on this or do you want to push it to next week?

[W95Psp]

@Nadrieril actually killed a whole bunch of issues in the frontend, so I don't think this issue is urgent any longer

[franziskuskiefer]

Ok, closing then