Fix scheduled WhatsApp messages sending as email; add 24h cleanup and recipient display

The scheduled-job store never persisted the channel field, so the
send worker always fell through to its email branch regardless of
what was requested. Also purges sent jobs 24h after sending instead
of keeping them forever, and surfaces who each scheduled job will go
to in the admin "manage scheduled" lists (now correctly filtered per
channel too).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

backend/src/controllers/whatsappBroadcastController.js

@@ -36,6 +36,22 @@ function parseFreeformPhones(lines) {
   return recipients;
 }
 
+// Human-readable summary of who a WhatsApp broadcast will go to, for the scheduled-jobs admin UI
+async function describeBroadcastRecipients({ userIds, phones }) {
+  const parts = [];
+  try {
+    const ids = Array.isArray(userIds) ? userIds.filter(x => typeof x === 'string' && x) : [];
+    if (ids.length) {
+      const users = await prisma.user.findMany({ where: { id: { in: ids } }, select: { name: true } });
+      const names = users.map(u => u.name).filter(Boolean);
+      parts.push(names.slice(0, 3).join(', ') + (names.length > 3 ? ` +${names.length - 3} more` : ''));
+    }
+    const extra = parseFreeformPhones(phones);
+    if (extra.length) parts.push(`${extra.length} phone number${extra.length === 1 ? '' : 's'}`);
+  } catch {}
+  return parts.length ? parts.join('; ') : 'No recipients';
+}
+
 // @desc    Preview WhatsApp broadcast recipients
 // @route   POST /api/whatsapp-broadcasts/preview
 // @access  Private/Supervisor or Admin
@@ -152,12 +168,15 @@ const scheduleWhatsAppBroadcast = async (req, res) => {
 
     const payload = { message, userIds, phones, eventId };
 
+    const recipientSummary = await describeBroadcastRecipients({ userIds, phones });
+
     const { addJob } = require('../utils/scheduledEmails');
     const created = addJob({
       broadcast: true,
       channel: 'whatsapp',
       scheduledAt: when.toISOString(),
       createdById: req.user?.id || null,
+      recipientSummary,
       payload,
     });