Add quick API smoke test to README.

Document a curl health-check command so contributors can verify the FastAPI service immediately after startup.

Made-with: Cursor

Author: adit24dhaya

README.md

@@ -156,6 +156,14 @@ uvicorn api.app:app --reload
 API base URL: `http://127.0.0.1:8000`  
 Swagger docs: `http://127.0.0.1:8000/docs`
 
+### Quick API smoke test
+
+After starting FastAPI, verify service health with:
+
+```bash
+curl -s http://127.0.0.1:8000/health
+```
+
 ## API Endpoints (Current)
 
 - `GET /health` -> Health status