Initial commit: Ananta CBT 4229938 private server with all fixes

Ananta.SDK/Rpc/HandlerAttribute.cs

@@ -0,0 +1,25 @@
+namespace Ananta.SDK.Rpc;
+
+public enum HandlerPacketKind
+{
+    Both,
+    Invoke,
+    Notify
+}
+
+/// <summary>
+/// Declares an incoming RPC endpoint. Method ids stay build-specific constants; the dispatcher is generic.
+/// By default a handler accepts both invoke and notify forms. Return helpers are safe no-ops for notifications.
+/// </summary>
+[AttributeUsage(AttributeTargets.Method, AllowMultiple = true, Inherited = false)]
+public sealed class HandlerAttribute : Attribute
+{
+    public uint MethodId { get; }
+    public HandlerPacketKind PacketKind { get; }
+
+    public HandlerAttribute(uint methodId, HandlerPacketKind packetKind = HandlerPacketKind.Both)
+    {
+        MethodId = methodId;
+        PacketKind = packetKind;
+    }
+}