make some overall QoL improvements

public/js/settings.js

@@ -1,7 +1,7 @@
 /**
  * @file Steuert die Einstellungsoberfläche für Darstellung, Konto, Personas und Diagnosen.
  */
-import { del, get, post, put } from "./api.js?v=20260909-account-controls";
+import { del, get, post, put, request } from "./api.js?v=20260909-account-controls";
 import {
     applyTheme as applySharedTheme,
     applyThemeMode as applySharedThemeMode,
@@ -65,7 +65,6 @@ const settingsPopupConfirm = $("settingsPopupConfirm");
 const settingsPopupTitle = $("settingsPopupTitle");
 const settingsPopupEyebrow = $("settingsPopupEyebrow");
 const settingsPopupDescription = $("settingsPopupDescription");
-const settingsPopupField = $("settingsPopupField");
 const settingsPopupInputLabel = $("settingsPopupInputLabel");
 const settingsPopupInput = $("settingsPopupInput");
 const settingsPersonaFields = {
@@ -500,9 +499,8 @@ usernameForm.addEventListener("submit", async (event) => {
         setNotice(res.error, "error");
         return;
     }
-    currentUsernameInput.value = res.username;
-    newUsernameInput.value = res.username;
     usernamePasswordInput.value = "";
+    if (!await loadProfile()) return;
     setNotice("Username updated.", "success");
 });