Toast Inc. is planning an initial public offering that could value the restaurant-software provider at around $20 billion. Toast tapped Goldman Sachs Group Inc. and JPMorgan Chase & Co. to underwrite a possible listing later this year. It could also consider other options including a sale or combination with a blank-check company, some of the people said. There are no guarantees Toast will eventually go public.In going public, Toast, a 10-year-old company whose valuation has jumped several fold in the past year, would join a red-hot IPO market powered lately by the high-profile debuts of companies including Affirm Holdings Inc. and Bumble Inc. Shares of both are trading far above their IPO prices, as are those of 2020 predecessors including Airbnb Inc. and DoorDash Inc. Also fueling the record IPO market is a wave of so-called special-purpose acquisition companies, which go public without a business and then hunt for one to merge with.