Add portable RV homes and decor prototype

inventory/player_hotbar.gd

@@ -314,6 +314,25 @@ func get_fish_slots() -> Array[StringName]:
 	return _fish_slots.duplicate()
 
 
+func find_item_slot(item_id: StringName) -> int:
+	return _slots.find(item_id)
+
+
+func find_first_empty_slot() -> int:
+	for slot_index: int in SLOT_COUNT:
+		if get_assignment_kind(slot_index) != AssignmentKind.EMPTY:
+			continue
+		if (
+			_inventory_layout == null
+			or _inventory_layout.get_key_at(
+				PlayerInventoryLayout.InventoryContainer.HOTBAR,
+				slot_index,
+			).is_empty()
+		):
+			return slot_index
+	return -1
+
+
 func replace_state(
 	slots: Array[StringName],
 	selected_slot: int,