fix(web_dashboard): 将时间参数从ISO格式转换为Unix时间戳

统一数据库查询中的时间参数格式，使用Unix时间戳替代ISO格式字符串，确保与数据库时间字段类型匹配

src/leadlag/web_dashboard.py

@@ -150,7 +150,7 @@ class TradingDashboard:
         conn = sqlite3.connect(db_path)
         cursor = conn.cursor()
         
-        # 计算时间范围
+        # 计算时间范围（转换为Unix时间戳）
         end_time = datetime.now()
         start_time = end_time - timedelta(hours=hours)
         
@@ -160,7 +160,7 @@ class TradingDashboard:
         FROM price_data 
         WHERE timestamp >= ? AND timestamp <= ?
         """
-        params = [start_time.isoformat(), end_time.isoformat()]
+        params = [start_time.timestamp(), end_time.timestamp()]
         
         if symbol:
             query += " AND symbol = ?"
@@ -196,7 +196,7 @@ class TradingDashboard:
         conn = sqlite3.connect(db_path)
         cursor = conn.cursor()
         
-        # 计算时间范围
+        # 计算时间范围（转换为Unix时间戳）
         end_time = datetime.now()
         start_time = end_time - timedelta(hours=hours)
         
@@ -208,7 +208,7 @@ class TradingDashboard:
         FROM trading_events 
         WHERE timestamp >= ? AND timestamp <= ?
         """
-        params = [start_time.isoformat(), end_time.isoformat()]
+        params = [start_time.timestamp(), end_time.timestamp()]
         
         if symbol:
             query += " AND symbol = ?"
@@ -259,7 +259,7 @@ class TradingDashboard:
         conn = sqlite3.connect(db_path)
         cursor = conn.cursor()
         
-        # 计算时间范围
+        # 计算时间范围（转换为Unix时间戳）
         end_time = datetime.now()
         start_time = end_time - timedelta(hours=hours)
         
@@ -267,7 +267,7 @@ class TradingDashboard:
         
         # 价格数据统计
         query = "SELECT COUNT(*) FROM price_data WHERE timestamp >= ? AND timestamp <= ?"
-        params = [start_time.isoformat(), end_time.isoformat()]
+        params = [start_time.timestamp(), end_time.timestamp()]
         if symbol:
             query += " AND symbol = ?"
             params.append(symbol)
@@ -277,7 +277,7 @@ class TradingDashboard:
         
         # 交易事件统计
         query = "SELECT event_type, COUNT(*) FROM trading_events WHERE timestamp >= ? AND timestamp <= ?"
-        params = [start_time.isoformat(), end_time.isoformat()]
+        params = [start_time.timestamp(), end_time.timestamp()]
         if symbol:
             query += " AND symbol = ?"
             params.append(symbol)
@@ -296,7 +296,7 @@ class TradingDashboard:
         FROM price_data 
         WHERE timestamp >= ? AND timestamp <= ?
         """
-        params = [start_time.isoformat(), end_time.isoformat()]
+        params = [start_time.timestamp(), end_time.timestamp()]
         if symbol:
             query += " AND symbol = ?"
             params.append(symbol)