Repackage pynac as a pip-installable package #30534
Description
Pynac has a compile-time dependency on the Python library
but is not installed using Python package infrastructure.
This is problematic because Python users cannot install it
using standard Python tools - for example for testing
different Python versions.
It would make sense for src/sage/libs/pynac/pynac.pxd and pynac_wrap.h to be shipped with this Python package, introducing a dependency on Cython. (The only thing blocking this is from sage.libs.gmp.types cimport mpz_t, mpq_t, mpz_ptr, mpq_ptr - but that can be fixed by some minimal cut&paste.)
(The other parts of src/sage/libs/pynac, constant.pxd, constant.pyx, pynac.pyx use various imports from sage and must remain in sage.libs.pynac)
Unfortunately, there is an unrelated project that has claimed the name "Pynac" on pypi.org: https://pypi.org/project/Pynac
Depends on #30446
Depends on #31064
Upstream: Reported upstream. No feedback yet.
CC: @rwst @slel @tobiasdiez @williamstein @kiwifb @tscrim @kliem @videlec @embray
Component: packages: standard
Keywords: pynac, sd110, sd111
Reviewer: François Bissey
Issue created by migration from https://trac.sagemath.org/ticket/30534