In the bitter rivalry between AI heavyweights OpenAI and Anthropic, it will mostly be who has the best technology that determines the ultimate victor. But which one of them gets to its public offering first matters a great deal, too. The window for initial public offerings is decidedly open, with a receptive market. Cerebras, an AI-chip company, rose 68% on its first day of trading last month. Only digital-design platform Figma’s absurd 250% rise last year was bigger for a company valued at more than $10 billion at listing in the past five years, according to FactSet data. Elon Musk’s SpaceX…