Summary: AskYourPDF adds multi-document chat feature

Why It Matters: Users can now pull information from many files at once instead of just one. This makes the tool more useful for complex research and large projects.

What Changed:

• Replaced the podcast generation announcement with a new "chat with multiple documents" feature.
• Updated the main call-to-action link to point to a new "Knowledge Base" documents page.
• Changed the hero section text to focus on turning complex PDFs into summaries for exams.
• Removed social media links and mobile app QR code text from the very bottom of the page.
• Updated internal links to remove the "www" prefix from the URL structure.