"fix:add-fallback-debug-log"

sync_data.py

@@ -337,7 +337,10 @@ def get_target_daily(code: str, start_date: str, market: str) -> Optional[pd.Dat
                     else:
                         bs_code = f"sz{code}"
                     df = get_stock_daily_baostock(bs_code, fetch_start, end_date)
+                    if df is not None:
+                        logger.debug(f"Got data from BaoStock for {code}")
                 if df is None:
+                    logger.debug(f"BaoStock failed or unavailable, falling back to AkShare for {code}")
                     df = ak.stock_zh_a_hist(symbol=code, period="daily", start_date=fetch_start, end_date=end_date, adjust="hfq")
             
             if df is not None and not df.empty: