add: aifast.club — direct-connect relay for 572+ AI models

[luwengwo]

What this changes

Checklist

• Edited data/providers.yaml (not the README tables directly)
• Followed data/schema.md
• status honest (unverified if I couldn't verify it myself)
• No referral/affiliate links, no marketing copy
• Claims have a dated source where non-obvious
• Bumped last_reviewed if this was a broad pass

Source / verification