Detect the :mod:`curses` mouse interface (:func:`~curses.getmouse`,
:func:`~curses.has_mouse`, the ``BUTTON*`` constants, and others) and the
window ``is_*`` state-query methods with configure capability probes or library
macros instead of gating them on ncurses-specific macros.  They are now also
available with other curses implementations that provide them, such as NetBSD
curses and PDCurses (the latter underpins ``windows-curses``).
