Admin health: push devices, pushes sent, expired devices and the last failure

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

server.js

@@ -687,6 +687,7 @@ async function handleRequest(req, res) {
       const checks = [probe('Seafile (Files)', SEAFILE_URL + '/api2/ping/'), probe('OnlyOffice', ONLYOFFICE_URL + '/healthcheck'), probe('Audiobooks', (process.env.OPENAUDIBLE_URL || AUDIOBOOKS_URL).replace(/\/$/, '') + '/'), probe('Podcasts (Podgrab)', PODCAST_URL)];
       if (recipes.enabled()) checks.push(probe('Recipes (Mealie)', (process.env.MEALIE_URL || 'https://mealie.necloud.us').replace(/\/+$/, '') + '/api/app/about'));
       out.services = await Promise.all(checks);
+      try { out.push = require('./push').health(); } catch { out.push = null; }
       out.lyrics = lyrics.enabled(); out.signal = signal.enabled(); out.transcripts = transcripts.status();
       res.writeHead(200, { 'content-type': 'application/json', 'cache-control': 'no-store' }); return res.end(JSON.stringify(out));
     }