to use
?(local server):
Yes you need a gamelogic named "server"
Gamelogics are local to the server only, so using one which you name server, is the normal done thing in mission making for specifying dedicated server code.
If this is for an addon, then instead you can
count playerside for east west, resistance & civilian
where the returned value is 0, then you have your dedicated server
And you shouldnt rely on any mission editor to read your readme and create a trigger, there is no need anyway and the above system will work around that
Other options are
?(local player):
?!(local player):
the problem with the above may be that your script might not work as intended when running a player/server configuration, eg the MP editor