ECS cargo telepad and cleanup (#6450)

Co-authored-by: metalgearsloth <metalgearsloth@gmail.com>

Content.Shared/Cargo/SharedCargoSystem.cs

@@ -0,0 +1,21 @@
+using System;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.Cargo;
+
+public abstract class SharedCargoSystem : EntitySystem {}
+
+[Serializable, NetSerializable]
+public enum CargoTelepadState : byte
+{
+    Unpowered,
+    Idle,
+    Teleporting,
+};
+
+[Serializable, NetSerializable]
+public enum CargoTelepadVisuals : byte
+{
+    State,
+};