fix: album cards use romaji index for album name display via _albumRomajiMap

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

src/api.js

@@ -69,18 +69,22 @@ export async function ndAuth() {
 // ─── ROMAJI INDEX ───
 // Fetched once per session from the backend, cached in memory.
 let _romajiIndex = null;
-let _romajiMap   = null; // Map<songId, { titleRomaji, artistRomaji, albumRomaji }>
+let _romajiMap      = null; // Map<songId, { titleRomaji, artistRomaji, albumRomaji }>
 let _artistRomajiMap = null; // Map<artistId, artistRomaji>
+let _albumRomajiMap  = null; // Map<albumName(JP), albumRomaji> — for album cards without song ID
 let _romajiIndexFetch = null; // in-flight promise dedup
 
 function _buildRomajiMap(idx) {
   const m  = new Map();
   const am = new Map();
+  const bm = new Map();
   if (Array.isArray(idx)) idx.forEach(e => {
     m.set(String(e.id), e);
     if (e.artistId && e.artistRomaji) am.set(String(e.artistId), e.artistRomaji);
+    if (e.album && e.albumRomaji && !bm.has(e.album)) bm.set(e.album, e.albumRomaji);
   });
   _artistRomajiMap = am;
+  _albumRomajiMap  = bm;
   return m;
 }
 
@@ -96,7 +100,7 @@ export async function fetchRomajiIndex() {
   return _romajiIndexFetch;
 }
 
-export function invalidateRomajiIndex() { _romajiIndex = null; _romajiMap = null; _artistRomajiMap = null; }
+export function invalidateRomajiIndex() { _romajiIndex = null; _romajiMap = null; _artistRomajiMap = null; _albumRomajiMap = null; }
 
 // ─── ROMAJI OVERRIDES ───
 // Stored server-side (shared across all clients). Cached in memory per session.
@@ -144,7 +148,8 @@ export function dispArtistById(id, name) {
 export function dispAlbumName(name) {
   if (!S.cfg.showRomaji) return name || '';
   const ov = getRomajiOverrides();
-  return ov[name] || name || '';
+  if (name && ov[name]) return ov[name];
+  return _albumRomajiMap?.get(name) || name || '';
 }
 
 // Synchronous lookup — returns index entry for a song ID, or null if not in index.