gh-152325: Gate curses.has_mouse() on the ncurses patch level (GH-152652)

gh-152325: Gate curses.has_mouse() on the ncurses patch level (GH-152652)

has_mouse() was added to ncurses after the 5.7 release, but the binding
guarded it only with NCURSES_MOUSE_VERSION, which 5.7 already defines, so
the module failed to compile against ncurses 5.7 (such as the system
curses on macOS).  Gate it additionally on NCURSES_EXT_FUNCS, which holds
the library's patch date.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>