Anthropic is upgrading Claude's free tier, apparently to capitalize on OpenAI's planned integration of ads into ChatGPT. On Wednesday, Anthropic said free Claude users can now create files, connect to external services, use skills and more.Anthropic added the ability for paid users to create files in September. Starting today, free users of the chatbot can also create and edit Excel spreadsheets, PowerPoint presentations, Word docs and PDFs. Claude's file creation abilities are powered by Sonnet...