feat(vercel): rewrite to .md when Accept: text/markdown

Author: sriramveeraghanta

vercel.json

@@ -104,5 +104,14 @@
       "source": "/self-hosting",
       "destination": "/self-hosting/overview"
     }
+  ],
+  "rewrites": [
+    {
+      "source": "/:path*",
+      "has": [
+        { "type": "header", "key": "accept", "value": ".*text/markdown.*" }
+      ],
+      "destination": "/:path*.md"
+    }
   ]
 }