equipment validation to race and form

[Vandivier]

today, a character can equip an item see #33

part of that is an item is equipped_to a location

eg

{
  "name": "sword",
  "equipped_to": "right hand"
}

but there's no validation or consideration of form. so a creature with no arms can equip to its right hand twice, which doesn't make sense

expansively consider form so that a human might have a "special grip form" where they can indeed have two swords in their right hand