chore: use spans instead

Server/AuthSession.cs

@@ -71,11 +71,10 @@ public class AuthSession : TcpSession
     protected override void OnReceived(byte[] buffer, long offset, long size)
     {
         _logger.LogDebug("Length: {Size} & offset: {Offset}", size, offset);
-        Span<byte> decryptedBuffer = new byte[size];
+        Span<byte> decryptedBuffer = stackalloc byte[(int)size];
 
         // xor every value after the first 8 bytes
-        var dataBuffer = Decrypt(new ArraySegment<byte>(buffer, 8, (int)size - 8).ToArray());
-
+        var dataBuffer = Decrypt(buffer.AsSpan(8, (int)size - 8));
         _logger.LogDebug("Length {Length}", BitConverter.ToUInt16(buffer, 0));
 
         var opCode = BitConverter.ToUInt16(buffer.ToArray(), 2);
@@ -99,7 +98,7 @@ public class AuthSession : TcpSession
         base.OnReceived(decryptedBuffer.ToArray(), offset, decryptedBuffer.Length);
     }
 
-    private static byte[] Decrypt(byte[] buffer)
+    private static Span<byte> Decrypt(Span<byte> buffer)
     {
         for (var i = 0; i < buffer.Length; ++i)
         {

Server/Packets/RawPacket.cs

@@ -8,10 +8,10 @@ namespace Server.Packets;
 [MessageUrn("packets")]
 public class RawPacket
 {
-    public RawPacket(OperationCode operationCode, byte[] messageBody, uint aliveTime, byte unknownValue2,
+    public RawPacket(OperationCode operationCode, Span<byte> messageBody, uint aliveTime, byte unknownValue2,
         byte unknownValue, Guid sessionId, AuthSession session)
     {
-        MessageBody = messageBody;
+        MessageBody = messageBody.ToArray();
         UnknownValue2 = unknownValue2;
         UnknownValue = unknownValue;
         SessionId = sessionId;