fix(ark): restore per-instance rconport launch parameter (#5210)

#4378 dropped rconport from the ARK start parameters, so extra instances on one install shared the RCON port from GameUserSettings.ini and failed to bind. Restore rconport in the default config and pass it as ?RCONPort so each instance config can set its own.

Fixes #4423

lgsm/config-default/config-lgsm/arkserver/_default.cfg

@@ -12,13 +12,14 @@
 ip="0.0.0.0"
 port="7777"
 queryport="27015"
+rconport="27020"
 # Default Map: TheIsland, Ragnarok, CrystalIsles, Aberration_P, ScorchedEarth_P, TheCenter, Extinction, Valguero_P, Genesis, Gen2
 defaultmap="TheIsland"
 altsavedirectoryname="${defaultmap}"
 
 ## Server Parameters | https://docs.linuxgsm.com/configuration/start-parameters#additional-parameters
 ## Game Server Docs | https://ark.wiki.gg/wiki/Server_configuration
-startparameters="${defaultmap}?AltSaveDirectoryName=${altsavedirectoryname} -MultiHome=${ip} -Port=${port} -QueryPort=${queryport} -AutoManagedMods -Crossplay -PublicIPForEpic=${publicip}"
+startparameters="${defaultmap}?AltSaveDirectoryName=${altsavedirectoryname}?RCONPort=${rconport} -MultiHome=${ip} -Port=${port} -QueryPort=${queryport} -AutoManagedMods -Crossplay -PublicIPForEpic=${publicip}"
 
 ## Extra Parameters | https://docs.linuxgsm.com/configuration/start-parameters#extra-parameters
 # Added to the end of startparameters.