Facebook is laying down a new gauntlet in its battle with Twitter to dominate online conversation around television: more data for broadcasters. This week, Facebook says it will begin sending weekly reports to America’s four largest television networks, offering a glimpse of how much chatter their shows are generating on the social network. The reports will reveal how many “actions” — likes, comments, or shares — a television episode has inspired on Facebook and how many members participated in an action. Facebook, which will not make the results generally available, will share the data reports with ABC, NBC, Fox, and CBS, and a small number of select partners. Facebook and Twitter are in a heated fight to own the Web’s town square, because becoming the go-to hub for real-time events like television shows could draw more user activity and more advertising dollars.