Updates Message Packets (#321)

### API Breaking Change
Combined `AsciiMessage` and `UnicodeMessage` into a single function that takes two arguments, `bool ascii` and `string lang`. Lang can be null (or anything) if ascii is true. 

- [X] Changes message packets
- [X] Cleans up some code
- [X] Uses benchmarks to determine if the spanwriter + copyfrom

Projects/Benchmarks/Packets/BenchmarkPacketBroadcast.cs

@@ -0,0 +1,183 @@
+using System;
+using System.Buffers;
+using System.Runtime.InteropServices;
+using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Jobs;
+using Server;
+using Server.Network;
+
+namespace Benchmarks
+{
+    [SimpleJob(RuntimeMoniker.NetCoreApp50)]
+    public class BenchmarkPacketBroadcast
+    {
+        public static int SendUnicodeMessage(
+            ArraySegment<byte>[] buffer,
+            Serial serial, int graphic, MessageType type, int hue, int font, string lang, string name, string text
+        )
+        {
+            name = name?.Trim() ?? "";
+            text = text?.Trim() ?? "";
+            lang = lang?.Trim() ?? "ENU";
+
+            if (hue == 0)
+            {
+                hue = 0x3B2;
+            }
+
+            var writer = new CircularBufferWriter(buffer);
+            writer.Write((byte)0xAE);
+            writer.Write((ushort)(50 + text.Length * 2));
+            writer.Write(serial);
+            writer.Write((short)graphic);
+            writer.Write((byte)type);
+            writer.Write((short)hue);
+            writer.Write((short)font);
+            writer.WriteAscii(lang, 4);
+            writer.WriteAscii(name, 30);
+            writer.WriteBigUniNull(text);
+
+            return writer.Position;
+        }
+
+        public static int CreateUnicodeMessage(
+            ref Span<byte> buffer,
+            Serial serial, int graphic, MessageType type, int hue, int font, string lang, string name, string text
+        )
+        {
+            name = name?.Trim() ?? "";
+            text = text?.Trim() ?? "";
+            lang = lang?.Trim() ?? "ENU";
+
+            if (hue == 0)
+            {
+                hue = 0x3B2;
+            }
+
+            var writer = new SpanWriter(buffer);
+            writer.Write((byte)0xAE);
+            writer.Write((ushort)(50 + text.Length * 2));
+            writer.Write(serial);
+            writer.Write((short)graphic);
+            writer.Write((byte)type);
+            writer.Write((short)hue);
+            writer.Write((short)font);
+            writer.WriteAscii(lang, 4);
+            writer.WriteAscii(name, 30);
+            writer.WriteBigUniNull(text);
+
+            return writer.Position;
+        }
+
+        private Pipe<byte>[] _pipes = new Pipe<byte>[512];
+        private IntPtr[] _pointers = new IntPtr[512];
+
+        [IterationSetup]
+        public void SetUp()
+        {
+            for (var i = 0; i < _pipes.Length; i++)
+            {
+                _pipes[i] = new Pipe<byte>(new byte[8192]);
+                _pointers[i] = Marshal.AllocHGlobal(8192);
+            }
+        }
+
+        [IterationCleanup]
+        public void CleanUp()
+        {
+            for (var i = 0; i < _pipes.Length; i++)
+            {
+                _pipes[i] = null;
+                Marshal.FreeHGlobal(_pointers[i]);
+            }
+        }
+
+        [Benchmark]
+        public int TestCircularBuffer()
+        {
+            var text = "This is some really long text that we want to handle. It should take a little bit to encode this.";
+            foreach (var pipe in _pipes)
+            {
+                var result = pipe.Writer.TryGetMemory();
+                var length = SendUnicodeMessage(
+                    result.Buffer,
+                    Serial.MinusOne, -1, MessageType.Regular, 0x3B2, 3, "ENU", "System", text
+                );
+                pipe.Writer.Advance((uint)length);
+            }
+
+            return _pipes.Length;
+        }
+
+        [Benchmark]
+        public int TestSpanWriterFromBuffer()
+        {
+            var text = "This is some really long text that we want to handle. It should take a little bit to encode this.";
+            foreach (var pipe in _pipes)
+            {
+                var result = pipe.Writer.TryGetMemory();
+
+                Span<byte> buffer = result.Buffer[0];
+
+                var length = CreateUnicodeMessage(
+                    ref buffer,
+                    Serial.MinusOne, -1, MessageType.Regular, 0x3B2, 3, "ENU", "System", text
+                );
+                pipe.Writer.Advance((uint)length);
+            }
+
+            return _pipes.Length;
+        }
+
+        [Benchmark]
+        public int TestSpanWriter()
+        {
+            var text = "This is some really long text that we want to handle. It should take a little bit to encode this.";
+            Span<byte> buffer = stackalloc byte[OutgoingMessagePackets.GetMaxMessageLength(text)];
+            var length = CreateUnicodeMessage(
+                ref buffer,
+                Serial.MinusOne, -1, MessageType.Regular, 0x3B2, 3, "ENU", "System", text
+            );
+
+            buffer = buffer.Slice(0, length);
+
+            foreach (var pipe in _pipes)
+            {
+                var result = pipe.Writer.TryGetMemory();
+                result.CopyFrom(buffer);
+                pipe.Writer.Advance((uint)buffer.Length);
+            }
+
+            return _pipes.Length;
+        }
+
+        [Benchmark]
+        public int TestSpanWriterAllocH()
+        {
+            var text = "This is some really long text that we want to handle. It should take a little bit to encode this.";
+
+            foreach (var pointer in _pointers)
+            {
+                Span<byte> buffer;
+                unsafe
+                {
+                    buffer = new Span<byte>(pointer.ToPointer(), 8192);
+                }
+
+                CreateUnicodeMessage(
+                    ref buffer,
+                    Serial.MinusOne,
+                    -1,
+                    MessageType.Regular,
+                    0x3B2,
+                    3,
+                    "ENU",
+                    "System",
+                    text
+                );
+            }
+
+            return _pipes.Length;
+        }
+    }
+}