Windows runners run as SYSTEM with the workspace under
C:\Windows\System32\config\systemprofile. cl.exe is 32-bit, so WOW64
file redirection sends its System32 access to SysWOW64 and it cannot
see the checked-out sources (C1083: aegis.h not found), while 64-bit
processes (git, python) see them fine. Move the Windows checkout/build
to C:\aeg-build.
Matrix job builds and tests wheels on linux/macos/windows (no Gitea
release, unlike mediahive); publish job uploads the merged dist/ to PyPI
only after all platforms succeed. release.py gains --no-upload for the
matrix jobs.
LeoVasanko