make emagged marker component (fixed version of #13867) (#14096)

* The all-in-one hacking solution
The thinking man's lockpick
The iconic EMAG

* emagged medbay's stasis bed

* left med, emagged sec' apc

* went back to chem, emagged the dispenser

* emagged the fax while i was there

* had a donut while waiting for emag to charge

* i broke into the bridge then announced 'mandatory johnson inspection in medical'

* get system instead of dependency

* feedback

* net suggestion

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

* use EnsureComp and import NetworkedComponent

---------

Co-authored-by: deltanedas <user@zenith>
Co-authored-by: deltanedas <deltanedas@laptop>
Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Content.Shared/Emag/Systems/EmagSystem.cs

@@ -156,12 +156,19 @@ namespace Content.Shared.Emag.Systems
         /// </summary>
         public bool DoEmagEffect(EntityUid user, EntityUid target)
         {
+            // prevent emagging twice
+            if (HasComp<EmaggedComponent>(target))
+                return false;
+
             var emaggedEvent = new GotEmaggedEvent(user);
             RaiseLocalEvent(target, ref emaggedEvent);
+
+            if (!emaggedEvent.Repeatable)
+                EnsureComp<EmaggedComponent>(target);
             return emaggedEvent.Handled;
         }
     }
 
     [ByRefEvent]
-    public record struct GotEmaggedEvent(EntityUid UserUid, bool Handled = false);
+    public record struct GotEmaggedEvent(EntityUid UserUid, bool Handled = false, bool Repeatable = false);
 }