Define frames for create session handshake

src/ArtemisNetCoreClient/ByteBuffer.cs

@@ -229,4 +229,10 @@ private string ReadAsShorts(int length)
         var value = _memoryStream.ReadByte();
         return value == DataConstants.NotNull ? ReadString() : null;
     }
+
+    public void WriteSize()
+    {
+        _memoryStream.TryGetBuffer(out var buffer);
+        BinaryPrimitives.WriteInt32BigEndian(buffer, buffer.Count - sizeof(int));
+    }
 }

src/ArtemisNetCoreClient/Framing/CreateSessionMessageV2.cs

@@ -0,0 +1,51 @@
+namespace ActiveMQ.Artemis.Core.Client.Framing;
+
+internal class CreateSessionMessageV2 : Packet
+{
+    public override byte Type => unchecked((byte) -18);
+    public required string Name { get; init; }
+    public long SessionChannelId { get; init; }
+    public int Version { get; init; }
+    public string? Username { get; init; }
+    public string? Password { get; init; }
+    public int MinLargeMessageSize { get; init; }
+    public bool Xa { get; init; }
+    public bool AutoCommitSends { get; init; }
+    public bool AutoCommitAcks { get; init; }
+    public bool PreAcknowledge { get; init; }
+    public int WindowSize { get; init; }
+    public string? DefaultAddress { get; init; }
+    public string? ClientId { get; init; }
+    public long ChannelId { get; init; }
+
+    public override void Encode(ByteBuffer buffer)
+    {
+        // header
+        buffer.WriteInt(0); // The length gets filled in at the end
+        buffer.WriteByte(Type);
+        buffer.WriteLong(ChannelId);
+
+        // rest
+        buffer.WriteString(Name);
+        buffer.WriteLong(SessionChannelId);
+        buffer.WriteInt(Version);
+        buffer.WriteNullableString(Username);
+        buffer.WriteNullableString(Password);
+        buffer.WriteInt(MinLargeMessageSize);
+        buffer.WriteBool(Xa);
+        buffer.WriteBool(AutoCommitSends);
+        buffer.WriteBool(AutoCommitAcks);
+        buffer.WriteInt(WindowSize);
+        buffer.WriteBool(PreAcknowledge);
+        buffer.WriteNullableString(DefaultAddress);
+        buffer.WriteNullableString(ClientId);
+
+        // size
+        buffer.WriteSize();
+    }
+
+    public override void Decode(ByteBuffer buffer)
+    {
+        throw new NotImplementedException();
+    }
+}

src/ArtemisNetCoreClient/Framing/CreateSessionResponseMessage.cs

@@ -0,0 +1,21 @@
+namespace ActiveMQ.Artemis.Core.Client.Framing;
+
+internal class CreateSessionResponseMessage : Packet
+{
+    public long ChannelId { get; private set; }
+    public int ServerVersion { get; private set; }
+
+    public override byte Type { get; } = 31;
+
+    public override void Encode(ByteBuffer buffer)
+    {
+        throw new NotImplementedException();
+    }
+
+    public override void Decode(ByteBuffer buffer)
+    {
+        _ = buffer.ReadByte(); // type
+        ChannelId = buffer.ReadLong();
+        ServerVersion = buffer.ReadInt();
+    }
+}

src/ArtemisNetCoreClient/Framing/Packet.cs

@@ -0,0 +1,8 @@
+namespace ActiveMQ.Artemis.Core.Client.Framing;
+
+internal abstract class Packet
+{
+    public abstract byte Type { get;  }
+    public abstract void Encode(ByteBuffer buffer);
+    public abstract void Decode(ByteBuffer buffer);
+}