When you use Facebook Messenger these days, a new prompt greets you with this come-on: “Ask Meta AI anything.” You may have opened the app to send a text to a pal, but Meta’s new artificial-intelligence-powered chatbot is tempting you with encyclopedic knowledge that’s just a few keystrokes away. Meta, the parent company of Facebook, has planted its home-grown chatbot on its WhatsApp and Instagram services. Now, billions of internet users can open one of these free social media platforms and draw on Meta AI’s services as a dictionary, guidebook, counselor or illustrator, among many other tasks…