Reboots, as the past few years have shown, are beloved by the TV business. This week’s makeover centers on the upfronts, a decades-old industry ritual revitalized by a new push into streaming ads. Beginning on Monday, a conga line of talent will take the stages (in stark contrast with the strike-afflicted 2023 edition), with more in-person presentations including the debuts of Netflix and Amazon. Here’s what to expect.