Convert domain verification to JSON format

domains/_vercel.jumpstone.json

@@ -1 +1,8 @@
-vc-domain-verify=jumpstone.is-a.dev,7d32b8cf215df4e1f144
+{
+    "owner": {
+        "username": "jumpstone"
+    },
+    "records": {
+        "TXT": "vc-domain-verify=jumpstone.is-a.dev,7d32b8cf215df4e1f144"
+    }
+}