engine: a Hanja word shows once, as every other candidate does

hanjaquery was the only query that assigned dictprefix's output straight
into im.kouho; emojiquery, dictqjp and katakouho all go through
addkouho, which is the only place a duplicate is dropped.  Two readings
under one prefix can carry the same word, and 198 of the 61,479 one- and
two-syllable prefixes in hanja.dict do: 게 listed 偈句 at rows 8 and 9,
개근 listed 皆勤狀 twice in five.

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

strans.c

@@ -653,14 +653,16 @@ emojiquery(void)
 static void
 hanjaquery(void)
 {
-	Str tail;
+	Str kouho[Maxkouho], tail;
+	int i, n;
 
 	transstr(im.l, &search.seed, &search.raw, &tail);
 	search.text = search.back;
 	sappend(&search.text, &tail);
 	clearkouho();
-	im.nkouho = dictprefix(getlang(LangHANJA)->dict, &search.text,
-		im.kouho, Maxkouho);
+	n = dictprefix(getlang(LangHANJA)->dict, &search.text, kouho, Maxkouho);
+	for(i = 0; i < n; i++)
+		addkouho(&kouho[i]);
 	selectfirst();
 }