Selectable Bar Signs (#29068)

* make bar sign selectable

* ajcm strongest soldier

* AJCM comes down hard for round 2

* good shit

* ok ballin

* bless'ed be the webedit

Content.Shared/BarSign/BarSignComponent.cs

@@ -1,10 +1,27 @@
 using Robust.Shared.GameStates;
 using Robust.Shared.Prototypes;
+using Robust.Shared.Serialization;
 
 namespace Content.Shared.BarSign;
 
 [RegisterComponent, NetworkedComponent, AutoGenerateComponentState(true)]
 public sealed partial class BarSignComponent : Component
 {
-    [DataField, AutoNetworkedField] public ProtoId<BarSignPrototype>? Current;
+    /// <summary>
+    /// The current bar sign prototype being displayed.
+    /// </summary>
+    [DataField, AutoNetworkedField]
+    public ProtoId<BarSignPrototype>? Current;
+}
+
+[Serializable, NetSerializable]
+public enum BarSignUiKey : byte
+{
+    Key
+}
+
+[Serializable, NetSerializable]
+public sealed class SetBarSignMessage(ProtoId<BarSignPrototype> sign) : BoundUserInterfaceMessage
+{
+    public ProtoId<BarSignPrototype> Sign = sign;
 }