feat: Only sync vars once?

lua/autorun/photon/shared/sh_simplenet.lua

@@ -173,17 +173,21 @@ if CLIENT then
 				ent[NET.Normalise(datum[1])] = NET.ReadFunctions[datum[2]](datum[3])
 			end
 		end
+		ent.HasBeenPhotonSimpleNetted = true
 	end)
 
 	net.Receive("Photon_SimpleNet_Change", function(len, ply)
 		local ent = net.ReadEntity()
 		local idx = net.ReadUInt(NET.Bits)
+		if not IsValid(ent) then
+			return PhotonWarning("Invalid Entity given in Photon_SimpleNet_Change")
+		end
 		local name, netType, extra = unpack(NET.FMap[idx])
 		ent[NET.Normalise(name)] = NET.ReadFunctions[netType](extra)
 	end)
 
 	hook.Add("NotifyShouldTransmit", "EMVU.Net.NotifyShouldTransmit", function(ent, shouldTransmit)
-		if shouldTransmit and ent.IsEMV and ent:IsEMV() then
+		if shouldTransmit and ent.IsEMV and ent:IsEMV() and not ent.HasBeenPhotonSimpleNetted then
 			net.Start("Photon_SimpleNet_Sync")
 			net.WriteEntity(ent)
 			net.SendToServer()