Add payment links (Stripe, Gumroad, Whop)

README.md

@@ -40,7 +40,9 @@ python app.py
 
 - **Demo**: Free on Hugging Face Spaces
 - **Full Source Code**: $39.99
-- Available on [Gumroad](https://gumroad.com) and [Whop](https://whop.com)
+- [Buy Now (Stripe)](https://buy.stripe.com/5kQcN5eTte2M7BCbzScZa1C)
+- [Buy on Gumroad](https://wealthybot8.gumroad.com/l/vphdus)
+- [Buy on Whop](https://whop.com/ai-content-repurposing-engine-api)
 
 ## 📄 License