fix: Add vercel.json redirect for framework-docs trailing slash

Author: GeneAI

website/vercel.json

@@ -0,0 +1,9 @@
+{
+  "redirects": [
+    {
+      "source": "/framework-docs/:path((?!.*\\.).+)",
+      "destination": "/framework-docs/:path/",
+      "permanent": true
+    }
+  ]
+}