fix(Core/Grid): Address bugs and performance issues introduced by visibility notifier implementation (#17480)

* Bug fixes

- Corrected std::chrono from seconds to milliseconds
- Got rid of leftover code that caused objects to not show up on time

* Removed logic to set gameobject as active

- More alignement with TC.
- Reduces CPU usage drastically

* Revert back to using time_t instead of std chrono

* Invoke SetNoCreate() method to reduce CPU usage drastically

* Remove setActive from static and motion transports

* Fix performance issues

* Added SetFarVisible to WG and some dungeon scripts

- Also removed setActive(true) from creatures in Wintergrasp. As for gameobjects they are set to active upon being damaged/destroyed and removed from active on rebuild (reset)

* Removed comments related to VISIBILITY_COMPENSATION

* Fix log

* Deleted unused files + corrected a check

* Added missing header

* Removed unused parameter

* Removed another unsued parameter

* Changed vector to set for i_visibleNow

- Changed vector to set for i_visibleNow in VisibleNotifer
- Adjusted HaveAtClient to accept Object*
- Adjusted SendUpdateToPlayer to send createobject packet only if not known to client

src/server/game/Battlefield/Battlefield.cpp

@@ -815,7 +815,7 @@ Creature* Battlefield::SpawnCreature(uint32 entry, float x, float y, float z, fl
 
     // Set creature in world
     map->AddToMap(creature);
-    creature->setActive(true);
+    creature->SetFarVisible(true);
 
     return creature;
 }
@@ -840,7 +840,7 @@ GameObject* Battlefield::SpawnGameObject(uint32 entry, float x, float y, float z
 
     // Add to world
     map->AddToMap(go);
-    go->setActive(true);
+    go->SetFarVisible(true);
 
     return go;
 }