## About The Pull Request
Acid, when applied to a turf, does not immediately apply acid to the
turfs contents, instead just doing that in the acid component.
The acid component now does not destroy things under a turf, like pipes.
Alien acid no longer instakills mobs, Fixes#69577 (Acid component now
has an option not to apply acid to mobs on a turf).
Aliens can now touch acid.
## Why It's Good For The Game
Fixes some bugs with aliens and acid.
I don't really like how the acid now does not damage mobs at all, but
that seems to be what is intended.
I don't think that acid should be going through a turfs contents in
different places, plus I like the look of it not immediately applying
the acid to them better.
## Changelog
🆑 Seven
balance: Acid on a turf no longer immediately applies acid to its
contents
fix: Acid applied on a tile will no longer damage pipes below that tile
fix: Xeno's corrosive acid no longer instakills mobs
fix: Xenos can now touch acid
/🆑
Loosely adapted from /vg/. This is an entity component system for adding behaviours to datums when inheritance doesn't quite cut it. By using signals and events instead of direct inheritance, you can inject behaviours without hacky overloads. It requires a different method of thinking, but is not hard to use correctly. If a behaviour can have application across more than one thing. Make it generic, make it a component. Atom/mob/obj event? Give it a signal, and forward it's arguments with a SendSignal() call. Now every component that want's to can also know about this happening.
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