Douglas Emmett Inc., the owner of one of the largest office complexes in Downtown Honolulu, is embarking on a multimillion-dollar effort to build nearly 500 more units at the Moanalua Hillside Apartments in Honolulu, Pacific Business News has learned. The California-based real estate investment trust, which owns the highly visible Bishop Square office complex, was issued 10 building permits for various types of work, including new foundations for the leasing office, maintenance building, guard shack…