[3dprinter-general] Cura 5.0 dependency mess fixes

[Gregor Riepl]

> Since it's broken in bookworm as well, I uploaded to unstable now.
> Once that has built there, I'll have a look what else needs to be
> refreshed.

Are you going to push the other Cura 5.0 packages to unstable as well?

I've rebuilt the affected packages locally (libnest2d, pynest2d and 
cura-engine), and it's running ok so far. Have yet to print something to 
see if everything works.

There's still these annoying messages about the broken AMFReader and 
TrimeshReader plugins, caused by the missing python3-trimesh module. I 
don't quite remember what the issue there was.