feat: Adds a memory mirrored ring buffer for networking. (#1533)

## Breaking Changes

Incoming packet registration signature has changed to:
```cs
delegate* void OnReceiveCallback(NetState state, SpanReader reader, int packetLength);

IncomingPackets.Register(int packetID, int length, bool ingame, OnReceiveCallback onReceive);
```

For example, an incoming packet handler signature would now look like this:
```cs
public static void SomeIncomingPacket(NetState state, SpanReader reader, int packetLength)
{
    // Parse the data
}
```

## Summary

Updates the network Pipe class to use a mirrored memory technique. This technique involves mapping the same physical memory to two contiguous virtual memory spaces so the byte buffer appears duplicated. This allows writing to a double-sized array to wrap around without the need for the `CircularBuffer` classes.

In practice this allows us to use `Span<byte>` as if the buffer was a regular array.


### Bug Fixes

- [X] Fixes bad fixed length string parsing

Projects/Server/Network/Packets/IncomingPackets.cs

@@ -13,6 +13,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  *************************************************************************/
 
+using System.Buffers;
 using System.Runtime.CompilerServices;
 
 namespace Server.Network;
@@ -25,7 +26,7 @@ public static class IncomingPackets
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static unsafe void Register(int packetID, int length, bool ingame,
-        delegate*<NetState, CircularBufferReader, int, void> onReceive) =>
+        delegate*<NetState, SpanReader, int, void> onReceive) =>
         Register(new PacketHandler(packetID, length, ingame, onReceive));
 
     public static void Register(PacketHandler packetHandler)