Fix subscription removal and broken xref.

Author: jeffhandley

docs/concepts/resources/resources.md

@@ -223,7 +223,7 @@ builder.Services.AddMcpServer()
     {
         if (ctx.Params?.Uri is { } uri)
         {
-            subscriptions.TryRemove(uri, out _);
+            subscriptions[ctx.Server.SessionId].TryRemove(uri, out _);
         }
         return new EmptyResult();
     });

docs/concepts/transports/transports.md

@@ -113,7 +113,7 @@ await using var client = await McpClient.ResumeSessionAsync(transport, new Resum
 
 #### Streamable HTTP server (ASP.NET Core)
 
-Use the `ModelContextProtocol.AspNetCore` package to host an MCP server over HTTP. The <xref:ModelContextProtocol.AspNetCore.McpEndpointRouteBuilderExtensions.MapMcp*> method maps the Streamable HTTP endpoint at the specified route (root by default). It also maps legacy SSE endpoints at `{route}/sse` and `{route}/message` for backward compatibility.
+Use the `ModelContextProtocol.AspNetCore` package to host an MCP server over HTTP. The <xref:Microsoft.AspNetCore.Builder.McpEndpointRouteBuilderExtensions.MapMcp*> method maps the Streamable HTTP endpoint at the specified route (root by default). It also maps legacy SSE endpoints at `{route}/sse` and `{route}/message` for backward compatibility.
 
 ```csharp
 var builder = WebApplication.CreateBuilder(args);