This week’s public market debut for tech startup ServiceTitan Inc. brought big windfalls for early investors — including returns of more than $1 billion for Iconiq Growth and over $800 million for Bessemer Venture Partners, according to people familiar with the matter. ServiceTitan, a Glendale, California-based software provider for the home services industry, finished its first day of trading at $101 a share on Thursday, a 42% boost from its listing price. The company has a fully diluted valuat...