Add builder service: scaffold, ASC API, devices UI, fastlane profile manager

Phase 1-3 of the builder subsystem on the Mac mini:
- Express + SQLite + sessions scaffolding, LAN-only service on port 3090
- App Store Connect JWT client (ES256 signing, devices/profiles/bundleIds)
- Device management UI with Apple-side registration
- Fastlane sigh wrapper with profile cache + auto-install to ~/Library/
- launchd plist + deploy script for Mac mini supervision

builder/public/js/devices.js

@@ -0,0 +1,83 @@
+const $ = (s) => document.querySelector(s);
+const esc = (s) => { const d = document.createElement('div'); d.textContent = s ?? ''; return d.innerHTML; };
+
+function toast(msg, kind = '') {
+  const t = $('#toast');
+  t.textContent = msg;
+  t.className = 'toast show ' + kind;
+  setTimeout(() => t.classList.remove('show'), 3500);
+}
+
+async function load() {
+  const res = await fetch('/api/devices');
+  if (res.status === 401) { location.href = '/login'; return; }
+  const devices = await res.json();
+  const container = $('#devices-container');
+
+  if (!devices.length) {
+    container.innerHTML = '<div class="card"><p style="color:var(--text-muted)">No devices registered yet.</p></div>';
+    return;
+  }
+
+  container.innerHTML = `
+    <table class="table">
+      <thead>
+        <tr><th>Name</th><th>UDID</th><th>Status</th><th>Added</th><th></th></tr>
+      </thead>
+      <tbody>
+        ${devices.map(d => `
+          <tr>
+            <td>${esc(d.name) || '<span class="mono" style="color:var(--text-muted)">unnamed</span>'}</td>
+            <td class="mono">${esc(d.udid)}</td>
+            <td>${d.synced_at
+              ? '<span class="badge synced">Synced</span>'
+              : '<span class="badge unsynced">Local only</span>'}</td>
+            <td class="mono">${esc(d.added_at)}</td>
+            <td><button class="delete-btn" data-udid="${esc(d.udid)}" title="Delete">&times;</button></td>
+          </tr>
+        `).join('')}
+      </tbody>
+    </table>
+  `;
+
+  container.querySelectorAll('.delete-btn').forEach(btn => {
+    btn.addEventListener('click', async () => {
+      if (!confirm('Remove this device locally? (It will remain in the Apple portal.)')) return;
+      const udid = btn.getAttribute('data-udid');
+      const r = await fetch(`/api/devices/${udid}`, { method: 'DELETE' });
+      if (r.ok) { toast('Removed', 'success'); load(); }
+      else toast('Delete failed', 'error');
+    });
+  });
+}
+
+$('#add-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  const form = e.target;
+  const body = {
+    udid: form.udid.value.trim(),
+    name: form.name.value.trim(),
+  };
+  const btn = form.querySelector('button[type=submit]');
+  btn.disabled = true;
+  btn.textContent = 'Registering…';
+
+  const r = await fetch('/api/devices', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify(body),
+  });
+  const data = await r.json().catch(() => ({}));
+  btn.disabled = false;
+  btn.textContent = 'Add Device';
+
+  if (r.ok) {
+    toast(data.synced ? 'Registered with Apple' : 'Saved locally (ASC not configured)', 'success');
+    form.reset();
+    load();
+  } else {
+    toast(data.error || 'Register failed', 'error');
+  }
+});
+
+load();