Implement clientless transports, Lua reload and same-map portals

Add native transport recording and execution with grid lifecycle handling, clientless teleport acknowledgements, and regression tests. Support targeted same-map portal imports and preserve disabled taxi nodes. Document live transport and portal verification and the remaining portal inventory.

src/server/game/Maps/Map.cpp

@@ -116,6 +116,27 @@ void Map::LoadAllCells()
             LoadGrid((cellX + 0.5f - CENTER_GRID_CELL_ID) * SIZE_OF_GRID_CELL, (cellY + 0.5f - CENTER_GRID_CELL_ID) * SIZE_OF_GRID_CELL);
 }
 
+void Map::LoadTransportGameObjectGrids()
+{
+    auto spawns = sObjectMgr->GetTransportGameObjectSpawns(GetId());
+    if (!spawns)
+        return;
+
+    uint32 grids = 0;
+    for (ObjectGuid::LowType spawnId : *spawns)
+    {
+        GameObjectData const* data = sObjectMgr->GetGameObjectData(spawnId);
+        if (!data || data->mapId != GetId() || !(data->spawnMask & (1u << GetSpawnMode())))
+            continue;
+        // Use the normal loader: respawns, pools, phases and spawn groups retain
+        // their existing rules. Loading an already loaded grid is idempotent.
+        if (EnsureGridLoaded(Cell(data->spawnPoint.GetPositionX(), data->spawnPoint.GetPositionY())))
+            ++grids;
+    }
+    TC_LOG_INFO("server.loading", "Initialized transport GameObject grids: map=%u instance=%u grids=%u candidates=%u",
+        GetId(), GetInstanceId(), grids, uint32(spawns->size()));
+}
+
 void Map::InitStateMachine()
 {
     si_GridStates[GRID_STATE_INVALID] = new InvalidState();