Merge pull request modelcontextprotocol#137 from imfing/fix-nav-link

fix: incorrect link for "Specification (Draft)" on nav bar

Author: jspahrsummers

docs/specification/draft/_index.md

@@ -4,6 +4,8 @@ cascade:
   type: docs
 breadcrumbs: false
 weight: 10
+aliases:
+  - /draft
 ---
 
 {{< callout type="info" >}}