Role ban UI updates (#16736)

Content.Shared/Players/MsgRoleBans.cs

@@ -0,0 +1,36 @@
+using Lidgren.Network;
+using Robust.Shared.Network;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.Players;
+
+/// <summary>
+/// Sent server -> client to inform the client of their role bans.
+/// </summary>
+public sealed class MsgRoleBans : NetMessage
+{
+    public override MsgGroups MsgGroup => MsgGroups.EntityEvent;
+
+    public List<string> Bans = new();
+
+    public override void ReadFromBuffer(NetIncomingMessage buffer, IRobustSerializer serializer)
+    {
+        var count = buffer.ReadVariableInt32();
+        Bans.EnsureCapacity(count);
+
+        for (var i = 0; i < count; i++)
+        {
+            Bans.Add(buffer.ReadString());
+        }
+    }
+
+    public override void WriteToBuffer(NetOutgoingMessage buffer, IRobustSerializer serializer)
+    {
+        buffer.WriteVariableInt32(Bans.Count);
+
+        foreach (var ban in Bans)
+        {
+            buffer.Write(ban);
+        }
+    }
+}