gh-85796: Build the curses module on Windows against PDCurses

The curses and _curses_panel modules are built when PDCURSES_DIR points
to a PDCursesMod source tree, linking it as a shared library so both
modules share one screen and panel stack.  PDCurses has no terminfo
database, so PC/pdcurses supplies the entry points the module needs.

curses.pdcurses_version reports the library version, as ncurses_version
already does.  What PDCurses provides is declared in one block, in the
same HAVE_CURSES_* terms that configure defines on Unix.

window.encoding follows the program locale, or is UTF-8 where PDCurses
is built to force it.  A cell holds a character on a wide build and a
locale byte on a narrow one, whichever library provides it.

test_curses covers the differences: PDCurses has its own color model,
supports one screen per process, and reports some errors differently.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: serhiy-storchaka

Doc/library/curses.rst

@@ -2211,6 +2211,17 @@ The :mod:`!curses` module defines the following data members:
 
    .. versionadded:: 3.8
 
+.. data:: pdcurses_version
+
+   A named tuple containing the three components of the PDCurses library
+   version: *major*, *minor*, and *patch*.  All values are integers.  The
+   components can also be accessed by name, so ``curses.pdcurses_version[0]``
+   is equivalent to ``curses.pdcurses_version.major`` and so on.
+
+   Availability: if the PDCurses library is used.
+
+   .. versionadded:: next
+
 .. data:: COLORS
 
    The maximum number of colors the terminal can support.

Include/py_curses.h

@@ -43,6 +43,14 @@
 #  define PDC_NCMOUSE
 #endif
 
+/* <windows.h>, which Python.h includes, defines MOUSE_MOVED as a console input
+   flag; PDCurses gives the name to a mouse event mask of its own.  The module
+   uses the curses one, so drop the Windows definition before the header below
+   redefines it. */
+#ifdef MOUSE_MOVED
+#  undef MOUSE_MOVED
+#endif
+
 /* On Solaris/illumos, the SVr4 <curses.h> does "typedef char bool;", which
    clashes with C's bool from <stdbool.h>.  Define _BOOL to suppress it, and
    include <stdbool.h> for the bool the header then needs.  ncurses ignores

Lib/test/test_curses.py

@@ -0,0 +1,3 @@
+The :mod:`curses` and :mod:`curses.panel` modules can now be built on Windows
+against a user-supplied `PDCurses <https://pdcurses.org/>`_ library by pointing
+the ``PDCURSES_DIR`` environment variable at its source tree.