merge JToric.jl into Oscar

[fingolfin]

No description provided.

[fingolfin]

One obstacle here is the dependency on CapAndHomalg, for the following reasons:

1. building it the first time takes several minutes, apparently mostly used for cloning a bunch of git repositories (Homalg, CAP, ...)
2. these git clones don't seem to use fixed commits, but rather track the master/main branches of the respective repositories. While that's great for developers who always get the latest version of the code, it's a bad idea for shipping code to end users, as they end up on quicksand (and we have a support nightmare at our hands)
3. in general, the "build" step for Julia packages is a flaky and unreliable affair; if that build step fails or is interrupted for whatever reason, Julia will still treat the package as installed and won't retry the build step; leaving people in a broken state. So at the very least, we (resp. CapAndHomalg) should perform some checks (during precompilation and/or __init__ to see if all packages/repos were properly cloned, and if not, do something about it (e.g. produce a helpful error telling the user to invoke Pkg.build; or try to fix the issue)
4. It needs to be made compatible with the upcoming GAP.jl 0.7
5. deal with SizeScreen override (see Restore screen size to SIZE_SCREEN_ORIGINAL homalg-project/CapAndHomalg.jl#23)

So overall, I think we need to either drop CapAndHomalg (but that seems to me like it would be substantial work, and perhaps not even possible), or else improve it to mitigate the points above (in collaboration with @mohamed-barakat)

[mohamed-barakat]

Thank you for summarizing the obstacles. As discussed during the phone call I will address these issues soon and ask for help where need.

[fingolfin]

Done (well, mostly, the GAP parts not, but that's incremental work)