Jetpacks (#9023)

* Movement acceleration

* tweaks

* Weightless refactor coz fuck it

* CCVars

* weightless movement tweaks

* Some cleanup while I'm here

* dorkpacks

* thanks fork

* fixes

* zoomies

* toggles

* hmm

* yamls

* b

* so true

* Effects refactor

* namespace

* review

Content.Server/Medical/MedicalScannerSystem.cs

@@ -14,6 +14,7 @@ using Content.Shared.DragDrop;
 using Content.Shared.Interaction;
 using Content.Shared.MobState.Components;
 using Content.Shared.Movement;
+using Content.Shared.Movement.Events;
 using Content.Shared.Preferences;
 using Content.Shared.Verbs;
 using Robust.Shared.Containers;