shopstate

shopstate:
    | "MAINMENU" -- The state used when the player is in the Main menu.
    | "BUYMENU" -- The state used when the player is in the Buy menu.
    | "SELLMENU" -- The state used when the player is selecting the storage they wish to sell items from.
    | "SELLING" -- The state used after the player has selected a storage and is now choosing items to sell.
    | "TALKMENU" -- The state used when the player is selecting a topic to talk about in the Talk menu.
    | "DIALOGUE" -- The state used when dialogue is occurring.
    | "LEAVE" -- The state used to initiate leaving the shop.
    | "LEAVING" -- The state used whilst the shop is transitioning out.