fix: iTunes route order (lookup before proxy); stable cover art URLs for browser caching

src/ui.js

@@ -1,6 +1,6 @@
 import { S } from './state.js';
 import { esc, formatDur, toast } from './utils.js';
-import { api, coverUrl, ndAuth, fetchRomajiIndex, romajiConvert, romajiLookup, invalidateRomajiIndex } from './api.js';
+import { api, coverUrl, ndAuth, fetchRomajiIndex, romajiConvert, romajiLookup, invalidateRomajiIndex, invalidateCoverCache } from './api.js';
 import { THEMES, applyTheme, getCurrentThemeId } from './themes.js';
 // Circular imports — safe (only used inside function bodies)
 import { playQueue, dlSongLocal, toggleStar, togglePlay, renderQueue, syncNpStar, updateStarBtn, npToggleStar, playCurrent, _syncNpDirect, setPlayIcon, nativeInsertAt, refreshDisplayMode } from './player.js';
@@ -78,7 +78,9 @@ export function saveSettings() {
   const pass = document.getElementById('s-pass').value;
   S.cfg.url       = document.getElementById('s-url').value.trim().replace(/\/$/,'');
   S.cfg.user      = document.getElementById('s-user').value.trim();
+  const credChanged = S.cfg.url !== document.getElementById('s-url').value.trim().replace(/\/$/,'') || !!pass;
   if(pass) S.cfg.pass = pass;
+  if(credChanged) invalidateCoverCache();
   S.cfg.lastfmKey        = document.getElementById('s-lastfm').value.trim();
   S.cfg.backendUrl       = document.getElementById('s-backend').value.trim().replace(/\/$/,'');
   S.cfg.showPlayCount = document.getElementById('s-show-playcount').classList.contains('on');