Frontend: ExtCreationModal: Use correct v-model

* Return to conditionally use correct v-model for permissions depending
  on is_editing, if is editing use formatted_permissions otherwise use
  the new_extension.permission to store correctly

core/frontend/src/components/kraken/modals/ExtensionCreationModal.vue

@@ -44,6 +44,14 @@
           />
 
           <v-textarea
+            v-if="is_editing"
+            v-model="formatted_permissions"
+            label="Original Settings"
+            :disabled="is_editing"
+            :rules="[validate_permissions]"
+          />
+          <v-textarea
+            v-else
             v-model="new_extension.permissions"
             label="Original Settings"
             :disabled="is_editing"
@@ -98,6 +106,9 @@ export default Vue.extend({
     form(): VForm {
       return this.$refs.form as VForm
     },
+    formatted_permissions() {
+      return JSON.stringify(JSON.parse(this.new_extension?.permissions ?? '{}'), null, 2)
+    },
     is_editing() {
       return this.extension?.editing ?? false
     },