Add Discord field and Vercel domain verification

Add a "discord" field to owner metadata in domains/miki.json and domains/_github-pages-challenge-michaelgyp.miki.json. Add a new domains/_vercel.miki.json file containing a TXT record for Vercel domain verification (vc-domain-verify=miki.is-a.dev,612724a8674f5ab7a4da).

domains/_github-pages-challenge-michaelgyp.miki.json

@@ -1,7 +1,8 @@
 {
     "owner": {
         "username": "michaelgyp",
-        "email": "michaeladventure080510@gmail.com"
+        "email": "michaeladventure080510@gmail.com",
+        "discord": "michaelgyp"
     },
     "records": {
         "TXT": "f87eb3e3615aef426f6ba56aa00ff8"

domains/_vercel.miki.json

@@ -0,0 +1,10 @@
+{
+    "owner": {
+        "username": "michaelgyp",
+        "email": "michaeladventure080510@gmail.com",
+        "discord": "michaelgyp"
+    },
+    "records": {
+        "TXT": "vc-domain-verify=miki.is-a.dev,612724a8674f5ab7a4da"
+    }
+}

domains/miki.json

@@ -1,7 +1,8 @@
 {
     "owner": {
         "username": "michaelgyp",
-        "email": "michaeladventure080510@gmail.com"
+        "email": "michaeladventure080510@gmail.com",
+        "discord": "michaelgyp"
     },
     "records": {
         "CNAME": "michaelgyp.github.io"