sagemathgh-38872: Native Windows build
    
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The goal of this PR is to provide a native Windows build of Sage using
MSVC (using the new Meson build system).

Instructions on how to test are under the `Windows` tab at https://doc-
pr-38872--sagemath.netlify.app/html/en/installation/meson.
Afterwards, you should be able to import some sage modules in a normal
`python` install (but most modules actually don't properly import due to
various errors that will be fixed peu a peu in follow-up PRs)

## State of Windows support of dependencies

- m4rie: upstream (https://github.com/malb/m4rie) doesn't provide win
build
- ec: not sure if upstream (https://github.com/JohnCremona/eclib)
provide win build
- ecm: upstream (https://gitlab.inria.fr/zimmerma/ecm) doesn't provide
native win build (only Cygwin)
- ntl: upstream provides win build (kind of), but it's not yet available
on conda (conda-forge/ntl-feedstock#16)
- maxima/ecl: upstream provides win build, but it's not yet available on
conda (conda-forge/maxima-feedstock#38)
- GAP: only cygiwn build exists https://github.com/gap-
system/gap/issues/4157
- [pari](http://pari.math.u-bordeaux.fr/pub/pari): now available on
conda (conda-forge/pari-feedstock#45)
- cypari2: no windows support yet
sagemath/cypari2#19
- lrcalc
- pplpy
- primecountpy
- fpylll
- rw
- cliquer
- lcalc
- ecl
- braiding
- gc
- homfly
- iml
- brial_groebner

## Conda Issues:
- Meson cannot find libraries without pkg-config files.
     - Workaround: Check that `set LIB` includes the conda env (e.g.
`...\.conda\envs\sage-dev\Library\lib`). If not, run `conda deactivate`
followed by `conda activate sage-dev` and then check again.
     - Alternatively, `set LIB=%CONDA_PREFIX%\Library\lib;%LIB%`
     - Possible upstream improvement: the compilers conda package should
set `LIB`
- If you don't have the debug version of Python installed, you may get
"LINK : fatal error LNK1104: cannot open file 'python311_d.lib'"
     - Workaround: `meson setup builddir -Dbuildtype=release`
     - Alternatively, in `<path to conda>\sage-dev\include\pyconfig.h`
uncomment: `//#       define Py_DEBUG` and change `python311_d.lib` to
`python311.lib`
     - Possible upstream improvement: conda should either ship a debug
version of python or a correct `pyconfig.h`
- conda-forge/gsl-feedstock#63
     - Workaround: Fallback to find_library in meson and/or change the
`gsl.pc` to match:
       ```
       prefix=C:/Users/Tobia/.conda/envs/sage-dev/Library
       exec_prefix=C:/Users/Tobia/.conda/envs/sage-dev/Library
       libdir=C:/Users/Tobia/.conda/envs/sage-dev/Library/lib
       sharedlibdir=C:/Users/Tobia/.conda/envs/sage-dev/Library/lib
       includedir=C:/Users/Tobia/.conda/envs/sage-dev/Library/include
       GSL_CBLAS_LIB=-lgslcblas

       Name: GSL
       Description: GNU Scientific Library
       Version: 2.7
       Libs: -L${libdir} -lgsl ${GSL_CBLAS_LIB}
       Cflags: -I${includedir}
       ```
- conda-forge/compilers-feedstock#66
     - Workaround: Run everything in "VS x64 Native Tools Command
Prompt" (for 64bit) or "Developer Command Prompt for VS2022 (or 2019)"
(for 32bit)
- conda-forge/libgd-feedstock#55
     - Workaround: Fallback to find_library in meson
- conda-forge/m4ri-feedstock#15
    - Workaround: Don't try to use m4ri on windows
- conda-forge/libflint-feedstock#38
    - Workaround: Don't try to use flint on windows

## Upstream issues
Singular
- Singular/Singular#1245
- Singular/Singular#1246
- Singular/Singular#1247

Flint:
- flintlib/flint#2100
- mingw-w64/mingw-w64#65 (indirectly since
pthread is flint dependency). Would be fixed by
conda-forge/libflint-feedstock#38.
   -> Workaround: Change `typedef __int64 pid_t;` to `typedef int
pid_t;` in `.conda\envs\sage-dev\Library\include\pthread_compat.h`
- flintlib/flint#2101:
   -> Workaround: disable compilation of fraction_field_FpT for now

Cysignals:
- sagemath/cysignals#207
- sagemath/cysignals#206


### 📝 Checklist

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- [ ] The title is concise and informative.
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- [ ] I have updated the documentation and checked the documentation
preview.

### ⌛ Dependencies

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URL: sagemath#38872
Reported by: Tobias Diez
Reviewer(s): Dima Pasechnik