Add a garbage collection component for grid movement (#7776)

If we move a station and there's thousands of bullets in the way we shouldn't just indefinitely lag the server as a result.

Content.Server/Shuttles/EntitySystems/SpaceGarbageSystem.cs

@@ -0,0 +1,28 @@
+using Content.Server.Shuttles.Components;
+using Robust.Shared.Physics;
+using Robust.Shared.Physics.Dynamics;
+
+namespace Content.Server.Shuttles.EntitySystems;
+
+/// <summary>
+///     Deletes anything with <see cref="SpaceGarbageComponent"/> that has a cross-grid collision with a static body.
+/// </summary>
+public sealed class SpaceGarbageSystem : EntitySystem
+{
+    public override void Initialize()
+    {
+        base.Initialize();
+        SubscribeLocalEvent<SpaceGarbageComponent, StartCollideEvent>(OnCollide);
+    }
+
+    private void OnCollide(EntityUid uid, SpaceGarbageComponent component, StartCollideEvent args)
+    {
+        var ourXform = Transform(args.OurFixture.Body.Owner);
+        var otherXform = Transform(args.OtherFixture.Body.Owner);
+
+        if (ourXform.GridID == otherXform.GridID ||
+            args.OtherFixture.Body.BodyType != BodyType.Static) return;
+
+        QueueDel(uid);
+    }
+}