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/MobMovementProfileEvent.cs

@@ -0,0 +1,35 @@
+namespace Content.Shared.Movement;
+
+/// <summary>
+/// Contains all of the relevant data for mob movement.
+/// Raised on a mob if something wants to overwrite its movement characteristics.
+/// </summary>
+[ByRefEvent]
+public struct MobMovementProfileEvent
+{
+    /// <summary>
+    /// Should we use this profile instead of the entity's default?
+    /// </summary>
+    public bool Override = false;
+
+    public readonly bool Touching;
+    public readonly bool Weightless;
+
+    public float Friction;
+    public float WeightlessModifier;
+    public float Acceleration;
+
+    public MobMovementProfileEvent(
+        bool touching,
+        bool weightless,
+        float friction,
+        float weightlessModifier,
+        float acceleration)
+    {
+        Touching = touching;
+        Weightless = weightless;
+        Friction = friction;
+        WeightlessModifier = weightlessModifier;
+        Acceleration = acceleration;
+    }
+}