Improve the demo feature of the project

gateway/app/middleware/auth.py

@@ -66,7 +66,11 @@ class AuthMiddleware(BaseHTTPMiddleware):
         if hasattr(request.state, "is_demo_session") and request.state.is_demo_session:
             if hasattr(request.state, "user") and request.state.user:
                 logger.info(f"✅ Demo session authenticated for route: {request.url.path}")
-                # Demo middleware already validated and set user context, pass through
+                # Demo middleware already validated and set user context
+                # But we still need to inject context headers for downstream services
+                user_context = request.state.user
+                tenant_id = user_context.get("tenant_id") or getattr(request.state, "tenant_id", None)
+                self._inject_context_headers(request, user_context, tenant_id)
                 return await call_next(request)
 
         # ✅ STEP 1: Extract and validate JWT token