finish rewrite; port to cmake, loads of other changes

Theres documentation at https://sylvessa.zip/fourkit/ now. And a bunch of other changes. Check the discord server for a more comprehensive list

Minecraft.Server.FourKit/Net/InetAddress.cs

@@ -0,0 +1,106 @@
+namespace Minecraft.Server.FourKit.Net;
+
+/// <summary>
+/// Represents an Internet Protocol (IP) address.
+/// </summary>
+public class InetAddress
+{
+    private readonly string _hostAddress;
+
+    internal InetAddress(string hostAddress)
+    {
+        _hostAddress = hostAddress ?? string.Empty;
+    }
+
+    /// <summary>
+    /// Returns the IP address string in textual presentation.
+    /// </summary>
+    /// <returns>The IP address as a string.</returns>
+    public string getHostAddress() => _hostAddress;
+
+    /// <summary>
+    /// Gets the host name for this IP address.
+    /// For this implementation, returns the IP address string.
+    /// </summary>
+    /// <returns>The host name.</returns>
+    public string getHostName() => _hostAddress;
+
+    /// <summary>
+    /// Returns the raw IP address of this InetAddress object as bytes.
+    /// </summary>
+    /// <returns>The raw IP address bytes, or an empty array if parsing fails.</returns>
+    public byte[] getAddress()
+    {
+        if (System.Net.IPAddress.TryParse(_hostAddress, out var ip))
+            return ip.GetAddressBytes();
+        return [];
+    }
+
+    /// <summary>
+    /// Checks whether this is a loopback address (127.x.x.x or ::1).
+    /// </summary>
+    /// <returns><c>true</c> if this is a loopback address.</returns>
+    public bool isLoopbackAddress()
+    {
+        if (System.Net.IPAddress.TryParse(_hostAddress, out var ip))
+            return System.Net.IPAddress.IsLoopback(ip);
+        return false;
+    }
+
+    /// <summary>
+    /// Checks whether this is a site-local (private) address.
+    /// </summary>
+    /// <returns><c>true</c> if this is a site-local address.</returns>
+    public bool isSiteLocalAddress()
+    {
+        if (!System.Net.IPAddress.TryParse(_hostAddress, out var ip))
+            return false;
+        byte[] bytes = ip.GetAddressBytes();
+        if (bytes.Length != 4) return false;
+        // 10.x.x.x, 172.16-31.x.x, 192.168.x.x
+        if (bytes[0] == 10) return true;
+        if (bytes[0] == 172 && bytes[1] >= 16 && bytes[1] <= 31) return true;
+        if (bytes[0] == 192 && bytes[1] == 168) return true;
+        return false;
+    }
+
+    /// <summary>
+    /// Checks whether this is a link-local address (169.254.x.x).
+    /// </summary>
+    /// <returns><c>true</c> if this is a link-local address.</returns>
+    public bool isLinkLocalAddress()
+    {
+        if (!System.Net.IPAddress.TryParse(_hostAddress, out var ip))
+            return false;
+        byte[] bytes = ip.GetAddressBytes();
+        if (bytes.Length != 4) return false;
+        return bytes[0] == 169 && bytes[1] == 254;
+    }
+
+    /// <summary>
+    /// Checks whether this is a multicast address (224-239.x.x.x).
+    /// </summary>
+    /// <returns><c>true</c> if this is a multicast address.</returns>
+    public bool isMulticastAddress()
+    {
+        if (!System.Net.IPAddress.TryParse(_hostAddress, out var ip))
+            return false;
+        byte[] bytes = ip.GetAddressBytes();
+        if (bytes.Length != 4) return false;
+        return bytes[0] >= 224 && bytes[0] <= 239;
+    }
+
+    /// <summary>
+    /// Checks whether this is the wildcard (any) address (0.0.0.0).
+    /// </summary>
+    /// <returns><c>true</c> if this is the wildcard address.</returns>
+    public bool isAnyLocalAddress()
+    {
+        if (System.Net.IPAddress.TryParse(_hostAddress, out var ip))
+            return ip.Equals(System.Net.IPAddress.Any) || ip.Equals(System.Net.IPAddress.IPv6Any);
+        return false;
+    }
+
+    /// <inheritdoc/>
+    public override string ToString() => _hostAddress;
+}