fix: dispArtistById prefers Navidrome sortName over kuromoji translation

Added _artistSortMap populated from getArtists (artist listing) and
getArtist (artist detail) responses. dispArtistById now checks the
Navidrome sort tag first, falls back to kuromoji only when missing.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/api.js

@@ -91,7 +91,8 @@ export async function ndAuth() {
 // Fetched once per session from the backend, cached in memory.
 let _romajiIndex = null;
 let _romajiMap      = null; // Map<songId, { titleRomaji, artistRomaji, albumRomaji }>
-let _artistRomajiMap = null; // Map<artistId, artistRomaji>
+let _artistRomajiMap = null; // Map<artistId, artistRomaji> — kuromoji backend
+let _artistSortMap   = null; // Map<artistId, sortName>    — Navidrome sort tag (preferred)
 let _albumRomajiMap  = null; // Map<albumName(JP), albumRomaji> — for album cards without song ID
 let _romajiIndexFetch = null; // in-flight promise dedup
 
@@ -121,7 +122,16 @@ export async function fetchRomajiIndex() {
   return _romajiIndexFetch;
 }
 
-export function invalidateRomajiIndex() { _romajiIndex = null; _romajiMap = null; _artistRomajiMap = null; _albumRomajiMap = null; }
+export function invalidateRomajiIndex() { _romajiIndex = null; _romajiMap = null; _artistRomajiMap = null; _artistSortMap = null; _albumRomajiMap = null; }
+
+// Populate _artistSortMap from Navidrome artist objects (OpenSubsonic sortName field).
+// Called whenever getArtists or getArtist data is loaded so dispArtistById can use it.
+export function cacheArtistSortNames(artists) {
+  if (!_artistSortMap) _artistSortMap = new Map();
+  for (const a of artists) {
+    if (a.id && a.sortName && !_isJp(a.sortName)) _artistSortMap.set(String(a.id), a.sortName);
+  }
+}
 
 // ─── ROMAJI OVERRIDES ───
 // Stored server-side (shared across all clients). Cached in memory per session.
@@ -164,6 +174,8 @@ export function dispArtistById(id, name) {
   if (!S.cfg.showRomaji) return name || '';
   const ov = getRomajiOverrides();
   if (name && ov[name]) return ov[name];
+  const sort = _artistSortMap?.get(String(id));
+  if (sort) return sort;
   return _artistRomajiMap?.get(String(id)) || name || '';
 }
 export function dispAlbumName(name) {

src/views/detail.js

@@ -1,6 +1,6 @@
 import { S } from '../state.js';
 import { esc, toast } from '../utils.js';
-import { api, coverUrl, itunesSearch, itunesLookupAlbum, itunesLookupArtistSongs, itunesLookupArtistAlbums, fetchRomajiIndex, dispArtistById } from '../api.js';
+import { api, coverUrl, itunesSearch, itunesLookupAlbum, itunesLookupArtistSongs, itunesLookupArtistAlbums, fetchRomajiIndex, dispArtistById, cacheArtistSortNames } from '../api.js';
 import { makeCard, makeAlbumCard, makeGlobalTrackItem, makeSongItem } from '../ui/components.js';
 import { playQueue, dlSongLocal, toggleStar, parseArtists } from '../player/player.js';
 import { showCtxMenu, openDlModal } from '../ui/ui.js';
@@ -99,7 +99,9 @@ export async function loadArtistDetail(artist) {
   // We reveal the hero with the album cover immediately, then patch in the artist photo async.
   const [albumRes] = await Promise.allSettled([albumP]);
 
-  const _firstAlbums = albumRes.status === 'fulfilled' ? (albumRes.value?.artist?.album || []) : [];
+  const _ndArtist = albumRes.status === 'fulfilled' ? albumRes.value?.artist : null;
+  if (_ndArtist) cacheArtistSortNames([_ndArtist]);
+  const _firstAlbums = _ndArtist?.album || [];
   const _bgCover = _firstAlbums[0] ? coverUrl(_firstAlbums[0].coverArt, 512) : null;
 
   const _revealHero = () => requestAnimationFrame(() => {
@@ -171,7 +173,7 @@ export async function loadArtistDetail(artist) {
   }
 
   // ── Top Songs ──
-  const ndAlbums    = albumRes.status === 'fulfilled' ? (albumRes.value?.artist?.album || []) : [];
+  const ndAlbums    = _ndArtist?.album || [];
   const topSongs    = topRes.status   === 'fulfilled' ? (topRes.value?.topSongs?.song  || []) : [];
   const iTracks     = iTracksRes.status === 'fulfilled' ? (iTracksRes.value || []).filter(t => t.wrapperType === 'track') : [];
   const iAlbums     = iAlbumsRes.status === 'fulfilled' ? (iAlbumsRes.value || []) : [];

src/views/home.js

@@ -1,6 +1,6 @@
 import { S } from '../state.js';
 import { esc } from '../utils.js';
-import { api, apiCached, apiIsCached, coverUrl, fetchRomajiIndex, dispArtistById } from '../api.js';
+import { api, apiCached, apiIsCached, coverUrl, fetchRomajiIndex, dispArtistById, cacheArtistSortNames } from '../api.js';
 import { makeCard, makeAlbumCard, makeSongItem } from '../ui/components.js';
 import { playQueue } from '../player/player.js';
 // Circular — safe (called inside event handlers)
@@ -202,6 +202,7 @@ export async function loadArtists() {
   try {
     const r = await apiCached('getArtists');
     const all = (r.artists?.index || []).flatMap(i => i.artist || []);
+    cacheArtistSortNames(all);
     if (S.cfg.showRomaji) await fetchRomajiIndex().catch(() => {});
     g.innerHTML = '';
     all.forEach(a => {