Store: Smashwords as a family-filtered book source; free audiobooks stream through the hub; extensions and Sites on Home

- Smashwords: free EPUBs from its shelf feed, filtered (adult/erotica flags, LGBTQ+, keywords, unlabelled romance); admin saves a Smashwords sign-in (encrypted) used to download
- LibriVox chapter audio is fetched and streamed by the hub (with seeking) instead of redirecting the browser to archive.org
- Home: a My apps section with installed extensions and Sites, also in the command palette

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

librivox.js

@@ -45,9 +45,22 @@ async function handle(req, res) {
       return json(res, 200, { items: items.map(b => ({ ...b, cover: b.cover ? `/api/ab/free/cover/${b.id}?u=${encodeURIComponent(b.cover)}` : '' })), more: lists.flat().length >= 20 });
     }
     if ((m = /^\/book\/(\d+)$/.exec(p)) && req.method === 'GET') return json(res, 200, publicBook(await book(m[1])));
-    if ((m = /^\/audio\/(\d+)\/(\d+)$/.exec(p)) && req.method === 'GET') { // the recording itself is on the Internet Archive; the browser is sent straight there (it supports seeking)
+    if ((m = /^\/audio\/(\d+)\/(\d+)$/.exec(p)) && req.method === 'GET') { // the recording is on the Internet Archive; the hub fetches it (redirects and all) and passes it on, with seeking
       const b = await book(m[1]), c = b.chapters[+m[2]]; if (!c) throw fail(404, 'No such chapter');
-      res.writeHead(302, { location: c.url, 'cache-control': 'private, max-age=600', 'referrer-policy': 'no-referrer' }); return res.end();
+      const ctl = new AbortController(); res.on('close', () => ctl.abort());
+      let url = c.url, r;
+      for (let i = 0; i < 6; i++) {
+        if (!allowed(url)) throw fail(502, 'That audio address is not allowed');
+        r = await fetch(url, { headers: { 'user-agent': 'NE-Hub/1.0', 'accept-encoding': 'identity', ...(req.headers.range ? { range: req.headers.range } : {}) }, redirect: 'manual', signal: ctl.signal }).catch(e => { throw fail(502, e.name === 'AbortError' ? 'Cancelled' : 'The Internet Archive did not answer'); });
+        if ([301, 302, 303, 307, 308].includes(r.status) && r.headers.get('location')) { url = new URL(r.headers.get('location'), url).href; try { await r.body?.cancel(); } catch {} continue; }
+        break;
+      }
+      if (r.status === 416) { res.writeHead(416, { 'content-range': r.headers.get('content-range') || 'bytes */0' }); return res.end(); }
+      if (!r.ok && r.status !== 206) throw fail(502, 'The Internet Archive answered ' + r.status + ' for that chapter');
+      const out = { 'content-type': /^audio\//.test(r.headers.get('content-type') || '') ? r.headers.get('content-type') : 'audio/mpeg', 'accept-ranges': 'bytes', 'cache-control': 'private, max-age=600', 'referrer-policy': 'no-referrer' };
+      for (const k of ['content-length', 'content-range']) if (r.headers.get(k)) out[k] = r.headers.get(k);
+      res.writeHead(r.status, out); if (!r.body) return res.end();
+      return require('stream').Readable.fromWeb(r.body).on('error', () => res.destroy()).pipe(res);
     }
     if ((m = /^\/cover\/(\d+)$/.exec(p)) && req.method === 'GET') {
       let cu = u.searchParams.get('u'); if (!cu || !allowed(cu)) { const b = await book(m[1]); cu = b.cover; } if (!cu || !allowed(cu)) throw fail(404, 'No cover');