fix use_inverse (aka wc_inverse) for curses

Highlighting for monsters shown due to extended monster detection and
for lava shown in black and white didn't work because that keys off
of 'iflags.use_inverse' (actually a macro for 'iflags.wc_inverse') and
curses wasn't enabling that window-capability option.  To be fair, it
was probably unconditional at the time the curses interface was first
developed.  It checked for whether a monster was supposed to be drawn
with inverse highlighting but wouldn't draw it that way because the
flag was always false.  Inverse b&w lava is relatively new and curses
hadn't been taught about it.

Various other things such as pets (if hilite_pet is on) and object
piles (if hilite_pile is on) get highlighted with inverse video when
use_color is off, regardless of whether use_inverse is on or off.
That's probably a bug.

win/curses/cursinit.c

@@ -810,6 +810,9 @@ curses_init_options()
 */
 #endif /* PDCURSES */
 
+    /* FIXME: this overrides explicit OPTIONS=!use_inverse */
+    iflags.wc_inverse = TRUE; /* aka iflags.use_inverse; default is False */
+
     /* fix up pet highlighting */
     if (iflags.wc2_petattr == -1) /* shouldn't happen */
         iflags.wc2_petattr = A_NORMAL;

win/curses/cursmain.c

@@ -29,7 +29,8 @@ extern long curs_mesg_suppress_turn; /* from cursmesg.c */
 /* Interface definition, for windows.c */
 struct window_procs curses_procs = {
     "curses",
-    (WC_ALIGN_MESSAGE | WC_ALIGN_STATUS | WC_COLOR | WC_HILITE_PET
+    (WC_ALIGN_MESSAGE | WC_ALIGN_STATUS | WC_COLOR | WC_INVERSE
+     | WC_HILITE_PET
 #ifdef NCURSES_MOUSE_VERSION /* (this macro name works for PDCURSES too) */
      | WC_MOUSE_SUPPORT
 #endif
@@ -675,6 +676,11 @@ curses_print_glyph(winid wid, XCHAR_P x, XCHAR_P y, int glyph,
             else
                 attr = A_REVERSE;
         }
+        /* water and lava look the same except for color; when color is off,
+           render lava in inverse video so that they look different */
+        if ((special & MG_BW_LAVA) && iflags.use_inverse) {
+            attr = A_REVERSE; /* mapglyph() only sets this if color is off */
+        }
     }
 
     curses_putch(wid, x, y, ch, color, attr);