Ports /tg/'s starlight luminance.

Because configuration is initialized before the map we also don't have the same runtimes issues corrected by https://github.com/tgstation/-tg-station/pull/7806.

code/controllers/configuration.dm

@@ -182,6 +182,8 @@
 	var/dooc_allowed = 1
 	var/dsay_allowed = 1
 
+	var/starlight = 0	// Whether space turfs have ambient light or not
+
 /datum/configuration/New()
 	var/list/L = typesof(/datum/game_mode) - /datum/game_mode
 	for (var/T in L)
@@ -603,6 +605,9 @@
 					config.event_delay_upper[EVENT_LEVEL_MODERATE] = MinutesToTicks(values[2])
 					config.event_delay_upper[EVENT_LEVEL_MAJOR] = MinutesToTicks(values[3])
 
+				if("starlight")
+					config.starlight = 1
+
 				else
 					log_misc("Unknown setting in configuration: '[name]'")