## About The Pull Request
Fixes#93280
It would give you the null rod arm, then equip the null rod, then try to
give you the null rod arm again, which removed your null rod arm and
caused... problems
## Changelog
🆑 Melbert
fix: Fixed chainsaw nullrod
/🆑
## About The Pull Request

Makes the chainsaw arm code generic, so you can attach any normal or
bulky sized item as an arm
Impl. detail:
Items-as-arms just use inhand sprites unless it has
`/datum/element/prosthetic_icon`. Currently used for chainsaws as the
only item with an implanted sprite.
Chainsaw arm nullrod now fully replaces the arm rather than being a
nodrop item.
When surgically adding any non-bodypart item, applying the item will
result in a loose fitting, and it might fall off on attack. The
following step (tape/suture) removes the fall chance.
## Why It's Good For The Game
Chainsaw arms are funny, but why stop at chainsaws beyond it being an
Evil Dead reference?
## Changelog
🆑 Melbert
add: Any normal or bulky sized item can be used as a prosthetic arm,
instead of just chainsaws.
/🆑