add no gui, no realtime mode, and train bash script

scripts/commons/Server.py

@@ -1,9 +1,10 @@
 import subprocess
 import os
+import time
 
 
 class Server():
-    def __init__(self, first_server_p, first_monitor_p, n_servers) -> None:
+    def __init__(self, first_server_p, first_monitor_p, n_servers, no_render=True, no_realtime=True) -> None:
         try:
             import psutil
             self.check_running_servers(psutil, first_server_p, first_monitor_p, n_servers)
@@ -17,21 +18,32 @@ class Server():
 
         # makes it easier to kill test servers without affecting train servers
         cmd = "rcssservermj"
+        render_arg = "--no-render" if no_render else ""
+        realtime_arg = "--no-realtime" if no_realtime else ""
         for i in range(n_servers):
             port = first_server_p + i
             mport = first_monitor_p + i
 
-            server_cmd = f"{cmd} -c {port} -m {mport} "
+            server_cmd = f"{cmd} -c {port} -m {mport} {render_arg} {realtime_arg}".strip()
 
-            self.rcss_processes.append(
-                subprocess.Popen(
-                    server_cmd.split(),
-                    stdout=subprocess.DEVNULL,
-                    stderr=subprocess.STDOUT,
-                    start_new_session=True
-                )
+            proc = subprocess.Popen(
+                server_cmd.split(),
+                stdout=subprocess.DEVNULL,
+                stderr=subprocess.STDOUT,
+                start_new_session=True
             )
 
+            # Avoid startup storm when launching many servers at once.
+            time.sleep(0.03)
+
+            rc = proc.poll()
+            if rc is not None:
+                raise RuntimeError(
+                    f"rcssservermj exited early (code={rc}) on server port {port}, monitor port {mport}"
+                )
+
+            self.rcss_processes.append(proc)
+
     def check_running_servers(self, psutil, first_server_p, first_monitor_p, n_servers):
         ''' Check if any server is running on chosen ports '''
         found = False