Best way to batch convert PPTX / PDFs to Markdown for AI Ingesrion

I have a repository of ~50 presentations that I want to feed into AI tools (Claude, Copilot, etc.) as a knowledge base. Rather than dumping raw PPTX or PDF files at it, I want to convert everything to Markdown so the AI can actually read and interpret the content cleanly. The key requirement is that it doesn't just strip out the text - ideally it also handles tables (converted to proper Markdown tables), diagrams and visual frameworks lik