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/ToggleJetpackEvent.cs

@@ -0,0 +1,8 @@
+using Content.Shared.Actions;
+
+namespace Content.Shared.Movement.Events;
+
+/// <summary>
+/// Raised on a jetpack whenever it is toggled.
+/// </summary>
+public sealed class ToggleJetpackEvent : InstantActionEvent {}