BRASILIA—Brazil’s government canceled an announcement for a generous new welfare program on Thursday, after a central bank currency intervention failed to calm market concerns about looser government spending ahead of next year’s election. President Jair Bolsonaro, who has seen his poll numbers fall over his mishandling of the pandemic, a weak economy, and rising inflation, summoned ministers for a 5 p.m. announcement of the new welfare program, according to a document seen by Reuters. But just minutes before the official release of the expanded welfare plan, which had spooked investors and deepened real losses against the dollar, the event was suspended, a spokesperson for the citizenship ministry said. The news of the expanded welfare plan came on the same day as a central bank intervention to prop up the real. The bank sold $500 million in a spot auction after a week of expanding currency swap sales that have failed …