PWA: install button, one icon badge for Signal, mail and tasks due, share target for files, manifest launch handler

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

public/settings.js

@@ -91,8 +91,9 @@ function viewSettings() {
     </div><div id="sec-signal"><h2>Signal alerts</h2><p class="sub">How this computer gets your attention when a Signal message arrives (not while you are looking at that chat). Saved on this device only.</p>
     <div class="list"><label class="row" style="cursor:pointer"><span class="grow"><b>Play a sound</b><small>A short chime</small></span><input type="checkbox" id="sga-s"></label>
       <label class="row" style="cursor:pointer"><span class="grow"><b>Desktop notification</b><small id="sga-ns">Pops up even when this tab is in the background</small></span><input type="checkbox" id="sga-n"></label></div>
-    <div class="bar"><button class="btn ghost" id="sga-t">Play test sound</button></div></div>${remindersHtml()}<h2>Install</h2><p class="sub">iPhone/iPad: Share → Add to Home Screen. Desktop Chrome/Edge: install icon in the address bar.</p></div>`;
+    <div class="bar"><button class="btn ghost" id="sga-t">Play test sound</button></div></div>${remindersHtml()}<h2>Install</h2>${installHtml()}</div>`;
   remindersInit();
+  installInit();
   // only show what this person may use
   const hide = (cond, sel) => { if (cond) document.querySelectorAll(sel).forEach(e => e.remove()); };
   hide(!((allowed('mail') && cfg.mail) || cfg.mailAdmin), '#sec-mail'); hide(!allowed('audio'), '#sec-audio'); hide(!allowed('signal'), '#sec-signal'); hide(!(allowed('files') || allowed('office')), '#row-sf, #out');
@@ -173,3 +174,19 @@ function viewSettings() {
   $('#hubout').onclick = async () => { try { mcClear(); for (const k of Object.keys(localStorage)) if (k.startsWith('dc:')) localStorage.removeItem(k); } catch {} await authPost('/api/auth/logout'); location.replace('/login'); };
   const out = $('#out'); if (out) out.onclick = () => { store.del('sf_token'); toast('Signed out'); viewSettings(); };
 }
+
+// ---- Install: the browser's own prompt where it offers one (Chrome, Edge, Android); iPhone/iPad have to use Share
+let installEvt = null;
+addEventListener('beforeinstallprompt', e => { e.preventDefault(); installEvt = e; const b = document.getElementById('install-btn'); if (b) installInit(); });
+addEventListener('appinstalled', () => { installEvt = null; const b = document.getElementById('install-box'); if (b) b.innerHTML = '<p class="sub">NE Hub is installed on this device.</p>'; });
+const isInstalled = () => matchMedia('(display-mode: standalone)').matches || navigator.standalone === true;
+function installHtml() {
+  const body = isInstalled() ? '<p class="sub">NE Hub is installed on this device.</p>'
+    : '<p class="sub">iPhone/iPad: Share → Add to Home Screen. Desktop Chrome/Edge: install icon in the address bar.</p><div class="bar"><button class="btn" id="install-btn" hidden>Install NE Hub</button></div>';
+  return '<div id="install-box">' + body + '</div>';
+}
+function installInit() {
+  const b = document.getElementById('install-btn'); if (!b || !installEvt) return;
+  b.hidden = false;
+  b.onclick = async () => { const ev = installEvt; installEvt = null; b.hidden = true; try { await ev.prompt(); } catch {} };
+}