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.Shared/Movement/Events/UpdateCanMoveEvent.cs

@@ -0,0 +1,17 @@
+using Content.Shared.Movement.Components;
+
+namespace Content.Shared.Movement.Events;
+
+/// <summary>
+///     Raised whenever <see cref="IMoverComponent.CanMove"/> needs to be updated. Cancel this event to prevent a
+///     mover from moving.
+/// </summary>
+public sealed class UpdateCanMoveEvent : CancellableEntityEventArgs
+{
+    public UpdateCanMoveEvent(EntityUid uid)
+    {
+        Uid = uid;
+    }
+
+    public EntityUid Uid { get; }
+}