[Feat&Fix] Система лежания (#288)

* лежать

* лучше так сделать

* - remove: Gravity is fine.

* - add: Hit moving lying targets.

* - tweak: Lie down insted of stun on FTL.

* - fix: Fix double component.

* - remove: Disable recoil.

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Co-authored-by: Aviu00 <aviu00@protonmail.com>

Content.Shared/Slippery/SlidingSystem.cs

@@ -1,5 +1,6 @@
 using Content.Shared.Movement.Events;
 using Content.Shared.Standing;
+using Content.Shared.Standing.Systems;
 using Content.Shared.Stunnable;
 using Robust.Shared.Physics.Events;