Refactors faction lists to use getters and setters and be cached (#94490)

code/modules/mob_spawn/ghost_roles/mining_roles.dm

@@ -320,7 +320,7 @@
 	implants = list(/obj/item/implant/weapons_auth)
 
 /datum/outfit/lavaland_syndicate/post_equip(mob/living/carbon/human/syndicate, visuals_only = FALSE)
-	syndicate.faction |= ROLE_SYNDICATE
+	syndicate.add_faction(ROLE_SYNDICATE)
 
 /datum/outfit/lavaland_syndicate/comms
 	name = "Lavaland Syndicate Comms Agent"

code/modules/mob_spawn/ghost_roles/spider_roles.dm

@@ -178,7 +178,7 @@
 	icon_state = "eggs"
 	you_are_text = "You are a flesh spider."
 	flavour_text = "An abomination of nature set upon the station by changelings. Your only goal is to kill, terrorize, and survive."
-	faction = list()
+	faction = null
 	directive = null
 	cluster_type = /obj/structure/spider/eggcluster/bloody
 	potentialspawns = list(

code/modules/mob_spawn/ghost_roles/unused_roles.dm

@@ -111,7 +111,7 @@
 	implants = list(/obj/item/implant/weapons_auth)
 
 /datum/outfit/syndicate_empty/post_equip(mob/living/carbon/human/H)
-	H.faction |= ROLE_SYNDICATE
+	H.add_faction(ROLE_SYNDICATE)
 
 //For ghost bar.
 /obj/effect/mob_spawn/ghost_role/human/space_bar_patron
@@ -314,7 +314,7 @@
 	implants = list(/obj/item/implant/weapons_auth)
 
 /datum/outfit/syndicatespace/post_equip(mob/living/carbon/human/syndie_scum)
-	syndie_scum.faction |= ROLE_SYNDICATE
+	syndie_scum.add_faction(ROLE_SYNDICATE)
 
 /datum/outfit/syndicatespace/syndicrew
 	name = "Syndicate Ship Crew Member"

code/modules/mob_spawn/mob_spawn.dm

@@ -76,7 +76,7 @@
 /obj/effect/mob_spawn/proc/special(mob/living/spawned_mob, mob/mob_possessor, apply_prefs)
 	SHOULD_CALL_PARENT(TRUE)
 	if(faction)
-		spawned_mob.faction = faction
+		spawned_mob.set_faction(faction)
 	if(ishuman(spawned_mob))
 		var/mob/living/carbon/human/spawned_human = spawned_mob
 		if(mob_species)