Christopher Vourlias Amazon Prime Video launched the latest chapter in its global expansion Thursday night in Nigeria with the flashy premiere of its first African Original, “Gangs of Lagos,” a gritty crime thriller from celebrated multi-hyphenate Jade Osiberu. At a packed house on Lagos’ ritzy Victoria Island, luminaries from the Nigerian film and fashion industries turned out to toast a movie that electrified the boisterous homegrown crowd ahead of its global release. “I’m overwhelmed,” said Osiberu after a rousing ovation. “It’s a dream come true.” “Gangs of Lagos,” which drops globally on Prime Video on Friday, is the first film to come out of the streamer’s three-year overall deal with Osiberu, the creator of domestic box-office sensations “Sugar Rush” and “Isoken” — one of a host of recent pacts with Nigerian creators from the U.S. tech giant as it tries to outflank Netflix in Africa’s biggest market.