Loadout citizenship restrictions (#21963)

Changes:
>  - rscadd: "Added citizenship loadout restrictions to the loadout."
> - rscadd: "Dominian Consular loadout items are now citizenship
restricted to the Empire of Dominia."
> - bugfix: "Religion loadout restrictions now actually restrict items
to religions."

Could prove useful and actually restricts what should be allowed to be
taken in the loadout if characters don't fit certain criteria. Proof of
concept presented the Empire of Dominia and their consular clothing.

code/modules/client/preference_setup/loadout/items/religion.dm

@@ -181,6 +181,7 @@ ABSTRACT_TYPE(/datum/gear/religion/dominia)
 	path = /obj/item/clothing/under/dominia/priest/consular
 	slot = slot_w_uniform
 	allowed_roles = list("Consular Officer")
+	citizenship = CITIZENSHIP_DOMINIA
 
 /datum/gear/religion/dominia/beret_consular
 	display_name = "tribunalist consular beret"
@@ -188,6 +189,7 @@ ABSTRACT_TYPE(/datum/gear/religion/dominia)
 	path = /obj/item/clothing/head/beret/dominia/consular
 	slot = slot_head
 	allowed_roles = list("Consular Officer")
+	citizenship = CITIZENSHIP_DOMINIA
 
 /datum/gear/religion/dominia/cape_consular
 	display_name = "tribunalist cousular cape"
@@ -195,6 +197,7 @@ ABSTRACT_TYPE(/datum/gear/religion/dominia)
 	path = /obj/item/clothing/accessory/poncho/dominia_cape/tribunalist/consular
 	slot = slot_wear_suit
 	allowed_roles = list("Consular Officer")
+	citizenship = CITIZENSHIP_DOMINIA
 
 /datum/gear/religion/dominia/codex
 	display_name = "tribunal codex"

code/modules/client/preference_setup/loadout/loadout.dm

@@ -245,7 +245,8 @@ GLOBAL_LIST_INIT(gear_datums, list())
 			&& (job && G.check_role(job.title)) \
 			&& G.check_culture(text2path(pref.culture)) \
 			&& G.check_origin(text2path(pref.origin)) \
-			&& G.check_religion(pref.religion))
+			&& G.check_religion(pref.religion)) \
+			&& G.check_citizenship(pref.citizenship)
 		var/ticked = (G.display_name in pref.gear)
 		var/style = ""
 
@@ -478,6 +479,13 @@ GLOBAL_LIST_INIT(gear_datums, list())
 	 */
 	var/religion
 
+	/**
+	 * A string of the citizenship that can use this item
+	 *
+	 * If left `null`, any citizenship can spawn with this item
+	 */
+	var/citizenship
+
 	/**
 	 * A `/list` of [/singleton/origin_item/culture] paths that can use this item
 	 */
@@ -545,11 +553,13 @@ GLOBAL_LIST_INIT(gear_datums, list())
 		return "You cannot spawn with the [initial(spawning_item.name)] with your current species!"
 	if(gd.faction_requirement && (human.employer_faction != "Stellar Corporate Conglomerate" && gd.faction_requirement != human.employer_faction))
 		return "You cannot spawn with the [initial(spawning_item.name)] with your current faction!"
-	var/our_culture = text2path(prefs.culture)
-	if(culture_restriction && !(our_culture in culture_restriction))
+	if(!check_religion(prefs.religion))
+		return "You cannot spawn with the [initial(spawning_item.name)] with your current religion!"
+	if(!check_citizenship(prefs.citizenship))
+		return "You cannot spawn with the [initial(spawning_item.name)] with your current citizenship!"
+	if(!check_culture(text2path(prefs.culture)))
 		return "You cannot spawn with the [initial(spawning_item.name)] with your current culture!"
-	var/our_origin = text2path(prefs.origin)
-	if(origin_restriction && !(our_origin in origin_restriction))
+	if(!check_origin(text2path(prefs.origin)))
 		return "You cannot spawn with the [initial(spawning_item.name)] with your current origin!"
 	return null
 
@@ -612,17 +622,24 @@ GLOBAL_LIST_INIT(gear_datums, list())
 	return TRUE
 
 // arg should be a religion name string
-/datum/gear/proc/check_religion(var/religion_)
-	if((religion && religion_))
-		if(islist(religion))
-			var/result = FALSE
-			for(var/religion_path in religion)
-				if(religion_path == religion_)
-					result = TRUE
-			return result
-		else if (religion != religion_)
-			return FALSE
-	return TRUE
+/datum/gear/proc/check_religion(var/user_religion)
+	if(!religion || !user_religion)
+		return TRUE
+	if(religion == user_religion)
+		return TRUE
+	if(islist(religion) && (user_religion in religion))
+		return TRUE
+	return FALSE
+
+// arg should be a citizenship name string
+/datum/gear/proc/check_citizenship(var/user_citizenship)
+	if(!citizenship || !user_citizenship)
+		return TRUE
+	if(citizenship == user_citizenship)
+		return TRUE
+	if(islist(citizenship) && (user_citizenship in citizenship))
+		return TRUE
+	return FALSE
 
 // arg should be a role name string
 /datum/gear/proc/check_role(var/role)