fix #H4035 - msg when wand zapped by mon explodes

fix #H4035 - msg when wand zapped by mon explodes

Message given when you see a cursed wand explode while being zapped
by a monster got suppressed if hero was deaf, even though there's no
reference to sound in that message.  Change it to ignore deafness;
also, change the alternate message when not visible (which uses
You_hear so already gets suppressed when deaf without caller worrying
about it) use "nearby" or "in the distance" with same criteria as
hearing a wand being zapped, instead of always "in the distance".

I also changed the near/far criteria:  threshold to be considered
"far" shrinks from 9 steps to 5 when there's no direct line of sight.