Add ModelContextProtocol.Core package (#428)

src/ModelContextProtocol/Protocol/JsonRpcError.cs

@@ -1,27 +0,0 @@
-using System.Text.Json.Serialization;
-
-namespace ModelContextProtocol.Protocol;
-
-/// <summary>
-/// Represents an error response message in the JSON-RPC protocol.
-/// </summary>
-/// <remarks>
-/// <para>
-/// Error responses are sent when a request cannot be fulfilled or encounters an error during processing.
-/// Like successful responses, error messages include the same ID as the original request, allowing the
-/// sender to match errors with their corresponding requests.
-/// </para>
-/// <para>
-/// Each error response contains a structured error detail object with a numeric code, descriptive message,
-/// and optional additional data to provide more context about the error.
-/// </para>
-/// </remarks>
-public class JsonRpcError : JsonRpcMessageWithId
-{
-    /// <summary>
-    /// Gets detailed error information for the failed request, containing an error code, 
-    /// message, and optional additional data
-    /// </summary>
-    [JsonPropertyName("error")]
-    public required JsonRpcErrorDetail Error { get; init; }
-}