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/Movement/Systems/JetpackSystem.cs

@@ -0,0 +1,48 @@
+using Content.Server.Atmos.Components;
+using Content.Server.Atmos.EntitySystems;
+using Content.Server.Movement.Components;
+using Content.Shared.Movement.Components;
+using Content.Shared.Movement.Systems;
+using Robust.Shared.Collections;
+using Robust.Shared.GameStates;
+
+namespace Content.Server.Movement.Systems;
+
+public sealed class JetpackSystem : SharedJetpackSystem
+{
+    private const float UpdateCooldown = 0.5f;
+
+    protected override bool CanEnable(JetpackComponent component)
+    {
+        return TryComp<GasTankComponent>(component.Owner, out var gasTank) && !(gasTank.Air.Pressure < component.VolumeUsage);
+    }
+
+    public override void Update(float frameTime)
+    {
+        base.Update(frameTime);
+
+        var toDisable = new ValueList<JetpackComponent>();
+
+        foreach (var (active, comp, gasTank) in EntityQuery<ActiveJetpackComponent, JetpackComponent, GasTankComponent>())
+        {
+            active.Accumulator += frameTime;
+            if (active.Accumulator < UpdateCooldown) continue;
+
+            active.Accumulator -= UpdateCooldown;
+
+            if (gasTank.Air.Pressure < comp.VolumeUsage)
+            {
+                toDisable.Add(comp);
+                continue;
+            }
+
+            gasTank.RemoveAirVolume(comp.VolumeUsage);
+            gasTank.UpdateUserInterface();
+        }
+
+        foreach (var comp in toDisable)
+        {
+            SetEnabled(comp, false);
+        }
+    }
+}