frontend/client: fix screen clear on Windows

artiq/frontend/artiq_client.py

@@ -5,6 +5,7 @@ import logging
 import time
 import asyncio
 import sys
+import os
 from operator import itemgetter
 from dateutil.parser import parse as parse_date
 
@@ -17,6 +18,9 @@ from artiq.tools import short_format
 
 
 def clear_screen():
+    if os.name == "nt":
+        os.system("cls")
+    else:
         sys.stdout.write("\x1b[2J\x1b[H")