Adds disposal mailing units (again) (#7630)

Content.Shared/Disposal/MailingUnitBoundUserInterfaceState.cs

@@ -0,0 +1,31 @@
+using Content.Shared.Disposal.Components;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.Disposal;
+
+[Serializable, NetSerializable]
+public sealed class MailingUnitBoundUserInterfaceState: BoundUserInterfaceState, IEquatable<MailingUnitBoundUserInterfaceState>
+{
+    public string? Target;
+    public List<string> TargetList;
+    public string? Tag;
+    public SharedDisposalUnitComponent.DisposalUnitBoundUserInterfaceState DisposalState;
+
+    public MailingUnitBoundUserInterfaceState(SharedDisposalUnitComponent.DisposalUnitBoundUserInterfaceState disposalState, string? target, List<string> targetList, string? tag)
+    {
+        DisposalState = disposalState;
+        Target = target;
+        TargetList = targetList;
+        Tag = tag;
+    }
+
+    public bool Equals(MailingUnitBoundUserInterfaceState? other)
+    {
+        if (ReferenceEquals(null, other)) return false;
+        if (ReferenceEquals(this, other)) return true;
+        return DisposalState.Equals(other.DisposalState)
+               && Target == other.Target
+               && TargetList.Equals(other.TargetList)
+               && Tag == other.Tag;
+    }
+}