HONG KONG — Lee Chun Ho’s voice cracked as he sat in the witness chair recounting the day that Hong Kong’s worst fire in decades tore through his apartment complex, killing his mother, his elder brother, his 15-month-old niece and the family’s live-in maid. Lee is one of dozens of people who have testified at public hearings in Hong Kong about the fire that killed 168 people at Wang Fuk Court in November.