After more than three centuries in business, the Onuma department store in the northern Japanese city of Yamagata began bankruptcy proceedings this year – one of many distinguished department stores across the country in dire straits.Known for fancy food halls, luxury items, impeccable service and, in their heyday, rooftop attractions to entertain families, Japan’s department stores have been in a long, slow decline as shopping habits change.Hong Kong’s Causeway Bay neighbourhood was once home…