fix(Core/Unit): Fix root/stun client freeze (#23521)

src/server/game/Entities/Unit/Unit.cpp

@@ -16709,6 +16709,13 @@ void Unit::StopMovingOnCurrentPos()
 
 void Unit::SendMovementFlagUpdate(bool self /* = false */)
 {
+    if (IsRooted())
+    {
+        // each case where this occurs has to be examined and reported and dealt with.
+        LOG_ERROR("Unit", "Attempted sending heartbeat with root flag for guid {}", GetGUID().ToString());
+        return;
+    }
+
     WorldPacket data;
     BuildHeartBeatMsg(&data);
     SendMessageToSet(&data, self);