Modernize GhostComponent & Ghost API (#36858)

* Move CanReturnToBody to system

* Move CanGhostInteract to system

* Cleanup redundant datafields and viewvariables

* Document datafields

* Document component

* Add SetTimeOfDeath Entity<T> overload, obsolete old version

* Document public methods

* Cleanup obsoleted method calls

Content.Server/Administration/Commands/AGhostCommand.cs

@@ -117,6 +117,6 @@ public sealed class AGhostCommand : LocalizedCommands
         }
 
         var comp = _entities.GetComponent<GhostComponent>(ghost);
-        ghostSystem.SetCanReturnToBody(comp, canReturn);
+        ghostSystem.SetCanReturnToBody((ghost, comp), canReturn);
     }
 }