Grafana dashboard step 동일화

src/services/summarizer.py

@@ -46,7 +46,6 @@ def compute_total_for_target(
     # --- Loki ---
     if is_loki(ds):
         try:
-            step_sec = 21600
             logger.info(f"[TARGET START] legend={label}, expr={expr}")
 
             # 1) 그대로 실행