say: one count rule everywhere, and a page she can explain (V-521)

The PR 113 review found four defects in one line file. Swept the other four
families and the Go side for the same four.

The JSON was clean: no undeclared placeholder, no abbreviation spoken, no
single-variant entry left unfixed. One register leak — page_blocked read
"robots.txt" out loud, which is a filename, not a reason he can act on.

The count rule was not clean. Four more copies of the three-way agreement
existed and two of them were wrong: ruPlural produced «1 минут назад» and
«5 часа назад» because formatTime spelled the noun out. pluralTasksRU was a
fifth copy. All of them now call say.CountWord. The pending-notification
summary picks the whole phrase, because the adjective declines with the noun.

internal/tasks/rank.go

@@ -263,21 +263,7 @@ func joinRU(rs []Ranked, limit int, withReasons bool) string {
 	s := strings.Join(parts, "; ")
 	if rest > 0 {
 		// With the noun. Spoken, a bare number trails off mid-sentence.
-		s += fmt.Sprintf("; и ещё %d %s", rest, pluralTasksRU(rest))
+		s += fmt.Sprintf("; и ещё %d %s", rest, say.CountWord(rest, "задача", "задачи", "задач"))
 	}
 	return s
 }
-
-// pluralTasksRU — the right form of "задача" for a count. Russian needs three.
-func pluralTasksRU(n int) string {
-	if n%100 >= 11 && n%100 <= 14 {
-		return "задач"
-	}
-	switch n % 10 {
-	case 1:
-		return "задача"
-	case 2, 3, 4:
-		return "задачи"
-	}
-	return "задач"
-}