We are adding a new skin category to the available wearable slots. This new slot
      will be used for wearables that shape the whole avatar. This will require changes to the
      Explorer to support the behavior of this new slot, which should hide several of the other
      slots (like head, upper_body, lower_body,
      feet and all the facial features). Also the Builder uses an outdated version of
      the ECS, and upgrading it to the latest one (which would support the new
      skin slot) is not possible at the moment. Finally, the Marketplace will require
      some way of displaying and browsing wearables of this new type a well, for this we will need
      to add the new slot to WearableCategory enum in @dcl/schemas so the
      nft-server can handle it, and also we need to add it to the schemas of both the
      marketplace and the collections subgraphs in all the supported
      networks (ethereum-mainnet, ethereum-ropsten,
      matic-mainnet and matic-mumbai).
    
      On the Explorer side, a new Skins section in the backpack will be added to list
      all the skins owned by the user. When selecting a skin, a confirmation modal will pop up
      explaining which other wearables will be hidden and prompting the user. Portable experiencies
      that would be hidden by skins will still continue working. When unequipping the skin, the
      hidden wearables should be visible again.
    
      On the Marketplace we will add a new section called skin, which will
      be accessible via the sidebar as "Skins", under the "Accessories"
      dropdown. This will end up passing a wearableCategory=skin param to the
      nft-server, which should filter by this wearableCategory the same
      way it does with the other ones.
    
      On the Builder editor, even though we can't upgrade to the latest version of the Explorer, we
      can still support this new slot behavior by doing some manipulation to the wearable before
      sending it to the ECS scene, and by limiting the categories that the user can add to the
      replaces and hides lists in the wearable's representations.
    
hides list on runtime are:headhairfacial_hairmoutheyebrowseyesupper_bodylower_bodyfeethides list using
        the editor are the following (aka "accesories"):
      earringeyewearhathelmetmasktiaratop_headreplaces list (the
        dropdown should be disabled when the wearable's category is skin and the list
        emptied).
      
      So, when we are about to render a wearable which is of category skin, we will add
      to all the representations the categories listed in 1) to the ones that the representation
      already has, if any, which are the ones described in 2).
    
      Finally, when deploying a wearable to a catalyst, the only categories that would be present in
      the hides list of any representation are the ones added by the creator (ie. all
      the "accesories" categories), and none of the ones hidden for all the
      skin wearables (ie. head, upper_body,
      lower_body, feet, etc), those should be hidden by default by the
      explorer and the builder editor themselves.