修复 NaN 值导致 JSON 序列化失败、K 线数据无法展示

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tushare/src/storage.py

@@ -68,6 +68,11 @@ def save_candles(df: pd.DataFrame, db_url: str = DEFAULT_DB_URL):
         df = df.copy()
         df = df.where(pd.notna(df), None)
         records = df.to_dict(orient="records")
+        # pandas float 列的 None 会被转为 NaN，需手动清理后再存入数据库
+        for record in records:
+            for key, val in record.items():
+                if isinstance(val, float) and val != val:  # NaN != NaN
+                    record[key] = None
         with conn.cursor() as cur:
             cur.executemany(
                 """