feat: integrate regional caravan persistence

tests/content_catalog_test.gd

@@ -47,8 +47,11 @@ func _test_core_pack() -> void:
 		"Core professions should enumerate by stable ID"
 	)
 	_check(
-		_item_ids(catalog.get_items()) == [&"food", &"herb", &"item_claw", &"item_sword", &"wood"],
-		"Core items should include legacy items and herbs in stable-ID order"
+		(
+			_item_ids(catalog.get_items())
+			== [&"food", &"herb", &"item_claw", &"item_sword", &"regional_trade_goods", &"wood"]
+		),
+		"Core items should include local and regional resources in stable-ID order"
 	)
 	_check(
 		_enemy_ids(catalog.get_enemies()) == [&"enemy_boar", &"enemy_raider", &"enemy_wolf"],
@@ -102,14 +105,22 @@ func _test_deterministic_enumeration_and_dependencies() -> void:
 	_check(
 		(
 			_item_ids(catalog.get_items())
-			== [&"amber", &"food", &"herb", &"item_claw", &"item_sword", &"wood"]
+			== [
+				&"amber",
+				&"food",
+				&"herb",
+				&"item_claw",
+				&"item_sword",
+				&"regional_trade_goods",
+				&"wood",
+			]
 		),
 		"Merged item enumeration should be globally stable-ID sorted"
 	)
 	var returned_items := catalog.get_items()
 	returned_items.clear()
 	_check(
-		catalog.get_items().size() == 6,
+		catalog.get_items().size() == 7,
 		"Callers should not be able to mutate the catalog's ordered arrays"
 	)