don't allow clicking on the invite link if they're not registered

src/views/ContactsView.vue

@@ -24,11 +24,27 @@
     <!-- New Contact -->
     <div id="formAddNewContact" class="mt-4 mb-4 flex items-stretch">
       <router-link
+        v-if="isRegistered"
         :to="{ name: 'invite-one' }"
         class="flex items-center bg-gradient-to-b from-green-400 to-green-700 shadow-[inset_0_-1px_0_0_rgba(0,0,0,0.5)] text-white px-1.5 py-1 mr-1 rounded-md"
       >
         <fa icon="envelope-open-text" class="fa-fw text-2xl" />
       </router-link>
+      <span
+        v-else
+        class="flex items-center bg-gradient-to-b from-slate-400 to-slate-700 shadow-[inset_0_-1px_0_0_rgba(0,0,0,0.5)] text-white px-1.5 py-1 mr-1 rounded-md"
+      >
+        <fa
+          icon="envelope-open-text"
+          class="fa-fw text-2xl"
+          @click="
+            danger(
+              'You must get registered before you can invite others.',
+              'Not Registered',
+            )
+          "
+        />
+      </span>
 
       <router-link
         :to="{ name: 'contact-qr' }"