sagemath: update deps (on top of #58320)

[tornaria]

• python3-Cython: patch for sage
• sagemath: update to 10.8.
• python3-cysignals: update to 1.12.6.
• python3-cypari2: update to 2.2.4.
• python3-gmpy2: update to 2.2.2.
• python3-memory_allocator: update to 0.2.0.
• m4ri: update to 20251207.
• m4rie: better changelog
• m4ri: update to 20260122.
• m4rie: rebuild for m4ri-20260122.
• brial: update to 1.2.15.
• ntl: update to 11.6.0.
• ntl: cross build.
• flintlib: update to 3.4.0.
• gap: update to 4.15.1.
• eclib: rebuild for ntl and flintlib
• singular: rebuild for ntl and flintlib
• sagemath: fix some tests
• sagemath: change sphinx

Testing the changes

• I tested the changes in this PR: briefly

This is based on #58320, updating dependencies that would need rebuilding sagemath.

I'm in the process of testing.

Missing / TODO:

• update maxima (see Update to maxima 5.49 sagemath/sage#40679)
• update ipykernel

[tornaria]

@dkwo you may want to try this.

In particular, I made ntl cross, could you make sure that cross built ntl works ok? We also need to adjust flintlib and singular templates so they are built with ntl on cross.

[dkwo]

Amazing that you got ntl to cross build!
is it possible to merge that change (and the bumps of singular etc) as a separate pr?
this way i could try to build sage with those packages from void repos and test if it works.

[dkwo]

This looks good to me.
@ahesford Perhaps this can be merged sometimes soon, so that at least sage is unbroken?

[ahesford]

If this is ready to go, please clean up the commits (especially squashing the separate sagemath commits) and drop the "draft" badge.

[tornaria]

@ahesford @dkwo this is now ready IMO.

Test failures are either transient (failed to download 'libpng-1.6.55_1' signature...) or some random failures in matrix_mod2_dense.pyx and matrix_integer_dense.pyx which have been around for a while and seem to get worse under load / CI.

[dkwo]

@tornaria I have just rebuilt sage natively on aarch64, using cross ntl from void's repo: all tests pass and I can use sage in jupyter lab. Do you understand why the build is failing for x86_64* on the builders? it looks like it does not find maxima Program maxima found: NO and rebuilds it.

[dkwo]

one difference is that on aarch64 maxima uses ecl.

[dkwo]

also, on ci here Program maxima found: YES (/usr/bin/maxima)

[dkwo]

Thanks!

[tornaria]

The issue is that we need maxima-ecl on makedepends. When using -Q this is not a problem because maxima-ecl is on checkdepends.