Evolve learn tabs

[Zimmi48]

This implements what was discussed during yesterday's meeting. This is on top of #59. Bikeshedding is authorized for the name of the "Rocq Prover and Platform features" tab (should it just be "Platform Docs" or "Features"?) and the "Supporting tools" tab.

The "Supporting tools" tab is a bit dry for now. In an upcoming (draft) PR, I attempt to fill it with existing guides from coq.inria.fr.

[mattam82]

@Zimmi48 @BastienSozeau how about tabs (link for the platforms on the left) for the different editors to quickly jump (and get at a glance all the available options). The current state with evolve-lear merged is here:
https://staging.rocq-prover.org/install#mac

[Zimmi48]

We discussed this option during the meeting last Wednesday, but we decided that tabs by operating system allowed to show OS-specific information about editors, and that this was better. Of course, it is still possible to revisit this decision (if I'm not the one to do the work 😉).

[mattam82]

I don't think that's incompatible, I would just like to see below "Set Up Your Editor" a list of links to all the editors available for the current chosen platform

[mattam82]

In any case, the proposed changes are already better than what we had, so I'll push to main

[Zimmi48]

I don't think that's incompatible, I would just like to see below "Set Up Your Editor" a list of links to all the editors available for the current chosen platform

OK, that's very do-able, I think.