Admin Tool: Observe entities in an extra viewport (#36969)

* camera

* add console command

* change verb name to camera

* placeholder text

* add button to player panel

* orks are indeed the best

* visibility flag fix

* not a datafield

* more follower fixes

* more cleanup

* add zooming

* resizing real

* remove commented out code

* remove AddForceSend

* comment

* Use OS window and add some comments

* fix comments and variable name

* Needs RT update

* Minor grammarchange

* Fix warning

* Cleanup

* almost working...

* fix bug

* oswindow update

* Remove need for RequestClosed.

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Co-authored-by: beck-thompson <beck314159@hotmail.com>
Co-authored-by: PJB3005 <pieterjan.briers+git@gmail.com>

Content.Shared/Follower/FollowerSystem.cs

@@ -189,6 +189,9 @@ public sealed class FollowerSystem : EntitySystem
     /// <param name="entity">The entity to be followed</param>
     public void StartFollowingEntity(EntityUid follower, EntityUid entity)
     {
+        if (follower == entity || TerminatingOrDeleted(entity))
+            return;
+
         // No recursion for you
         var targetXform = Transform(entity);
         while (targetXform.ParentUid.IsValid())