Add 3-arg RequestContext constructor and obsolete 2-arg to eliminate null-forgiving operator usage

Co-authored-by: halter73 <54385+halter73@users.noreply.github.com>
Agent-Logs-Url: https://github.com/modelcontextprotocol/csharp-sdk/sessions/43f266c7-392e-40c4-a808-759fb46d04d5

Author: Copilot

tests/ModelContextProtocol.Tests/Server/McpServerToolTests.cs

@@ -569,10 +569,7 @@ public async Task OutputSchema_Options_CallToolResult_PreservesStructuredContent
             OutputSchema = outputSchema,
         });
         var mockServer = new Mock<McpServer>();
-        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest())
-        {
-            Params = new CallToolRequestParams { Name = "tool" },
-        };
+        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest(), new CallToolRequestParams { Name = "tool" });
 
         var result = await tool.InvokeAsync(request, TestContext.Current.CancellationToken);
 
@@ -650,10 +647,7 @@ public async Task OutputSchema_Attribute_CallToolResult_PreservesStructuredConte
         Assert.Equal("object", tool.ProtocolTool.OutputSchema.Value.GetProperty("type").GetString());
 
         var mockServer = new Mock<McpServer>();
-        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest())
-        {
-            Params = new CallToolRequestParams { Name = "tool" },
-        };
+        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest(), new CallToolRequestParams { Name = "tool" });
 
         var result = await tool.InvokeAsync(request, TestContext.Current.CancellationToken);
 
@@ -727,10 +721,7 @@ public async Task OutputSchema_Options_PersonType_WithCallToolResult()
             SerializerOptions = serializerOptions,
         });
         var mockServer = new Mock<McpServer>();
-        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest())
-        {
-            Params = new CallToolRequestParams { Name = "tool" },
-        };
+        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest(), new CallToolRequestParams { Name = "tool" });
 
         var result = await tool.InvokeAsync(request, TestContext.Current.CancellationToken);
 
@@ -753,10 +744,7 @@ public async Task OutputSchema_Options_OverridesReturnTypeSchema_InvokeAndValida
             SerializerOptions = serializerOptions,
         });
         var mockServer = new Mock<McpServer>();
-        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest())
-        {
-            Params = new CallToolRequestParams { Name = "tool" },
-        };
+        var request = new RequestContext<CallToolRequestParams>(mockServer.Object, CreateTestJsonRpcRequest(), new CallToolRequestParams { Name = "tool" });
 
         var result = await tool.InvokeAsync(request, TestContext.Current.CancellationToken);