Improve the design of the frontend 2

shared/clients/data_client.py

@@ -298,6 +298,11 @@ class DataServiceClient(BaseServiceClient):
         )
         
         # Use POST request with extended timeout
+        logger.info("Making traffic data request", 
+                   url="traffic/historical", 
+                   tenant_id=tenant_id, 
+                   timeout=traffic_timeout.read)
+        
         result = await self._make_request(
             "POST",
             "traffic/historical", 
@@ -310,7 +315,8 @@ class DataServiceClient(BaseServiceClient):
             logger.info(f"Successfully fetched {len(result)} traffic records")
             return result
         else:
-            logger.error("Failed to fetch traffic data")
+            logger.error("Failed to fetch traffic data - _make_request returned None")
+            logger.error("This could be due to: network timeout, HTTP error, authentication failure, or service unavailable")
             return []
     
     # ================================================================