ci: add a note on performance

Author: Tony

README.md

@@ -7,3 +7,8 @@ This repo contains the source code of my portfolio website.
 ### [API Source Code](https://github.com/tonybnya/portfolio-api)
 
 ### [Admin Panel Source Code](https://github.com/tonybnya/portfolio-api-admin-panel)
+
+
+> **Note on performance:**
+> This service is hosted on Render’s free tier, which may introduce a cold-start delay on first request.
+> In production, this would be deployed on an always-on plan to guarantee low latency.