Merge main branch and resolve conflicts

Co-authored-by: eiriktsarpalis <[email protected]>

Author: Copilot

src/ModelContextProtocol.AspNetCore/StreamableHttpHandler.cs

@@ -250,7 +250,6 @@ private static Task WriteJsonRpcErrorAsync(HttpContext context, string errorMess
     {
         var jsonRpcError = new JsonRpcError
         {
-            Id = default,
             Error = new()
             {
                 Code = errorCode,

src/ModelContextProtocol.Core/Protocol/JsonRpcMessageWithId.cs

@@ -26,5 +26,5 @@ private protected JsonRpcMessageWithId()
     /// Each ID is expected to be unique within the context of a given session.
     /// </remarks>
     [JsonPropertyName("id")]
-    public required RequestId Id { get; set; }
+    public RequestId Id { get; set; }
 }

tests/ModelContextProtocol.AspNetCore.Tests/StatelessServerTests.cs

@@ -203,7 +203,6 @@ public static async Task<string> TestSamplingErrors(McpServer server)
 
         var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => server.SendRequestAsync(new JsonRpcRequest
         {
-            Id = default,
             Method = RequestMethods.SamplingCreateMessage
         }));
         return ex.Message;
@@ -222,7 +221,6 @@ public static async Task<string> TestRootsErrors(McpServer server)
 
         var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => server.SendRequestAsync(new JsonRpcRequest
         {
-            Id = default,
             Method = RequestMethods.RootsList
         }));
         return ex.Message;
@@ -241,7 +239,6 @@ public static async Task<string> TestElicitationErrors(McpServer server)
 
         var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => server.SendRequestAsync(new JsonRpcRequest
         {
-            Id = default,
             Method = RequestMethods.ElicitationCreate
         }));
         return ex.Message;