Fix UserNameDialog open error and add defensive ref check

- Added ref="userNameDialog" to UserNameDialog in AccountViewView.vue template
- Patched onEditName() to check for dialog ref and open() method before calling
- Improved error notification to use NotificationIface fields (group, type, title, text)
- Prevents "Cannot read properties of undefined (reading 'open')" error if dialog is missing

src/components/IdentitySection.vue

@@ -185,4 +185,3 @@ export default class IdentitySection extends Vue {
   }
 }
 </script>
-