Add ShowRules commmand (#5908)

Content.Shared/Info/SharedRulesManager.cs

@@ -0,0 +1,26 @@
+using JetBrains.Annotations;
+using Lidgren.Network;
+using Robust.Shared.Network;
+
+namespace Content.Shared.Info;
+
+public abstract class SharedRulesManager
+{
+    [UsedImplicitly]
+    public sealed class ShowRulesPopupMessage : NetMessage
+    {
+        public override MsgGroups MsgGroup => MsgGroups.Command;
+
+        public float PopupTime { get; set; }
+
+        public override void ReadFromBuffer(NetIncomingMessage buffer)
+        {
+            PopupTime = buffer.ReadFloat();
+        }
+
+        public override void WriteToBuffer(NetOutgoingMessage buffer)
+        {
+            buffer.Write(PopupTime);
+        }
+    }
+}