Sergei 3a20d5cc08 Add security middleware to backend
Security features:
- Helmet: Security headers (XSS, clickjacking protection)
- CORS: Whitelist only allowed domains
- Rate Limiting: 100 req/15min general, 5 req/15min for auth
- Stripe webhook signature verification (already had)
- Admin API key protection (already had)

Allowed origins:
- wellnuo.smartlaunchhub.com
- wellnuo.com
- localhost (dev)
- Expo dev URLs

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
2025-12-19 09:50:27 -08:00
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2025-12-19 09:50:27 -08:00