✨ 添加定时任务日志管理功能

- 添加用户清空日志按钮
- 添加30天自动清理定时任务执行日志
- 简化日志API代码，移除调试日志

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

database.py

@@ -1706,3 +1706,27 @@ def get_user_all_schedule_logs(user_id, limit=50):
             LIMIT ?
         ''', (user_id, limit))
         return [dict(row) for row in cursor.fetchall()]
+
+
+def delete_schedule_logs(schedule_id, user_id):
+    """删除指定定时任务的所有执行日志（需验证用户权限）"""
+    with db_pool.get_db() as conn:
+        cursor = conn.cursor()
+        cursor.execute('''
+            DELETE FROM schedule_execution_logs
+            WHERE schedule_id = ? AND user_id = ?
+        ''', (schedule_id, user_id))
+        conn.commit()
+        return cursor.rowcount
+
+
+def clean_old_schedule_logs(days=30):
+    """清理指定天数前的定时任务执行日志"""
+    with db_pool.get_db() as conn:
+        cursor = conn.cursor()
+        cursor.execute('''
+            DELETE FROM schedule_execution_logs
+            WHERE execute_time < datetime('now', '-' || ? || ' days')
+        ''', (days,))
+        conn.commit()
+        return cursor.rowcount