Unknown prices stay unknown
The directory no longer files a tool as paid only because nobody had checked its free tier. Claude and
ChatGPT are out of that list, and 65 freemium tools now show under Free tier.

Fixes and improvements
- A tool whose free tier we haven't checked is no longer listed as paid only
- 65 freemium and free tools now show up under Free tier
- A price we haven't recorded shows as a blank, not a zero or a no
- The AI-readable versions of each page and the MCP server say not recorded instead of no