Meta gives its AI agent away for free. OpenAI launched theirs 21 days later at $100 a month. Same product category, opposite prices, and only one of these companies can afford to lose money on agents. Here's the economics underneath. Every dot runs on its own cloud computer and keeps working after you close the laptop. That single design choice breaks the subscription math that built ChatGPT. A chatbot costs OpenAI money when you type. A dot costs them money while you sleep. Meta can eat that…