Polish: npm test runs every test file, two silent failures now log, Loading placeholders shimmer

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

public/audiobooks-view.js

@@ -61,7 +61,7 @@ const abLoadProg = async () => { try { for (const [id, p] of Object.entries(awai
 
 async function viewBooks(args = []) {
   const v = $('#view');
-  v.innerHTML = '<div class="wrap"><h1>Audiobooks</h1><p class="empty">Loading…</p></div>';
+  v.innerHTML = '<div class="wrap"><h1>Audiobooks</h1><p class="empty loading" role="status">Loading…</p></div>';
   try {
     const [data] = await Promise.all([abApi('/books'), abLoadProg(), lvPrime()]);
     abBooks = Array.isArray(data) ? data : (data.books || Object.values(data));
@@ -105,7 +105,7 @@ function abSheet(b) {
   if (el.querySelector('#abh')) el.querySelector('#abh').onclick = () => { closeSheet(); shareMedia({ kind: 'audiobook', title: abTitle(b), sub: abAuthor(b), art: abCover(b), link: '#/audio/book/' + encodeURIComponent(id) }); };
   if (el.querySelector('#abs')) el.querySelector('#abs').onclick = () => go(0);
   el.querySelector('#abc').onclick = async () => {
-    const box = el.querySelector('#abch'); box.innerHTML = '<p class="empty">Loading…</p>';
+    const box = el.querySelector('#abch'); box.innerHTML = '<p class="empty loading" role="status">Loading…</p>';
     const ch = await abChapters(id);
     box.innerHTML = ch.length ? ch.map((c, i) => `<button class="row" data-i="${i}"><span class="grow"><b>${esc(c.title)}</b><small>${abFmt(c.start)}</small></span></button>`).join('') : '<p class="empty">This book has no chapter list.</p>';
     box.querySelectorAll('button[data-i]').forEach(x => x.onclick = () => go(ch[x.dataset.i].start));