fix: mermaid diagram syntax for endpoints

README.md

@@ -50,9 +50,9 @@ graph TB
     
     subgraph "Serving Layer"
         F --> G[FastAPI Service]
-        G --> H["/predict"]
-        G --> I["/predictions"]
-        G --> J["/health"]
+        G --> H[predict endpoint]
+        G --> I[predictions endpoint]
+        G --> J[health endpoint]
     end
     
     subgraph "Frontend"