docs: update readme

README.md

@@ -76,7 +76,7 @@ Note: the creator cannot see their post with the copied link (except in private
 - Data is **never written to disk**
 - All data is lost on server restart
 - CSRF protection via double-submit cookie pattern
-- Rate limiting: 10 requests per minute per IP
+- Rate limiting: 10 requests per IP (resets on server restart)
 - Security headers: CSP, X-Frame-Options, X-Content-Type-Options, Referrer-Policy
 - 10MB maximum paste size limit
 - Intended for ephemeral sharing only — do not store sensitive data