refactor: enhance Optuna backtesting framework, optimize orderbook filtering, and update database management utilities.

scratch/check_ws_ob4.py

@@ -0,0 +1,16 @@
+from database import TradeDB
+db = TradeDB()
+try:
+    sql = """
+    SELECT DATE(recv_ts) as dt, source, COUNT(*) as cnt 
+    FROM ws_orderbook 
+    GROUP BY dt, source
+    ORDER BY dt DESC
+    LIMIT 10
+    """
+    rows = db.conn.execute(sql).fetchall()
+    print("OB DATES:", [dict(r) for r in rows])
+except Exception as e:
+    print(f"ERROR: {e}")
+finally:
+    db.close()