Label night-session products and hide day-only symbols at night.

Mark tradable varieties with a night tag; during 21:00-02:30 filter out index futures and other products without night sessions from symbol picker and recommend list.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/check_server_night.py

@@ -0,0 +1,16 @@
+import paramiko
+import sys
+sys.stdout.reconfigure(encoding="utf-8", errors="replace")
+c = paramiko.SSHClient()
+c.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+c.connect("192.168.8.21", username="root", password="woaini88", timeout=15)
+for cmd in [
+    "ls -la /opt/qihuo/market_sessions.py",
+    "head -5 /opt/qihuo/market_sessions.py",
+    "cd /opt/qihuo && /opt/qihuo/venv/bin/python -c \"import market_sessions; print(market_sessions.is_night_trading_session())\"",
+]:
+    _, o, e = c.exec_command(cmd)
+    print(">>>", cmd)
+    print(o.read().decode())
+    print(e.read().decode())
+c.close()