The newspaper comic is among the most ephemeral of art forms, but for almost 30 years a mural featuring cartoon characters has been lovingly preserved by the owners of a bar in New York City. The longtime showpiece of Costello’s, at 225 East Forty-fourth Street, was a wall decorated by America’s most famous cartoonists, but when the bar’s owner sold it earlier this year, the mural seemed in danger of going the way of yesterday’s crossword.