feat(win): Windows build support

[codercms]

Inspired by https://github.com/pgvector/pgvector

Tested on Win 11, MSVS 2022 (MSVC 19), built for PostgreSQL 18

P.S. Also tested that it keep working on Ubuntu 24.04, built for PostgreSQL 17 (using clang 19)

P.P.S. Build fails on MINGW 64 for PostgreSQL 17+ but that's out of scope of this PR (its unrelated to changes introduced by this PR):

D:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/15.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: src/pg_cron.o:pg_cron.c:(.text+0x158b): undefined reference to `libintl_ngettext'
collect2.exe: error: ld returned 1 exit status
make: *** [D:/msys64/mingw64/lib/postgresql/pgxs/src/makefiles/../../src/Makefile.shlib:319: pg_cron.dll] Error 1

But could be easy fixed by patching Makefile's SHLIB_LINK = $(libpq) to SHLIB_LINK = $(libpq) -lintl

Closes #22
Closes #323

[codercms]

@microsoft-github-policy-service agree