feat: lunch cron endpoints — reminders + recap

Both endpoints follow the existing GET + x-cron-secret pattern. Per-event
try/catch ensures one failing event does not poison the sweep.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/api/cron/lunch-reminders/route.ts

@@ -0,0 +1,73 @@
+import { NextResponse, type NextRequest } from 'next/server'
+import { prisma } from '@/lib/prisma'
+import { sendLunchReminderEmail } from '@/lib/email'
+
+/**
+ * Cron: send a single reminder email per attending member who hasn't picked
+ * a lunch dish yet, when we're inside the reminder window
+ * (deadline - reminderHoursBeforeDeadline) <= now < deadline.
+ *
+ * Idempotent — `LunchEvent.reminderSentAt` blocks repeat sends.
+ */
+export async function GET(request: NextRequest): Promise<NextResponse> {
+  const cronSecret = request.headers.get('x-cron-secret')
+  if (!cronSecret || cronSecret !== process.env.CRON_SECRET) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+  const now = new Date()
+  const events = await prisma.lunchEvent.findMany({
+    where: {
+      enabled: true,
+      reminderSentAt: null,
+      reminderHoursBeforeDeadline: { not: null },
+      eventAt: { not: null },
+    },
+  })
+  let sent = 0
+  for (const event of events) {
+    try {
+      if (!event.eventAt || event.reminderHoursBeforeDeadline == null) continue
+      const deadline = new Date(
+        event.eventAt.getTime() - event.changeCutoffHours * 3_600_000,
+      )
+      const reminderAt = new Date(
+        deadline.getTime() - event.reminderHoursBeforeDeadline * 3_600_000,
+      )
+      if (now < reminderAt || now >= deadline) continue
+
+      const ams = await prisma.attendingMember.findMany({
+        where: {
+          confirmation: {
+            project: { programId: event.programId },
+            status: 'CONFIRMED',
+          },
+          lunchPick: { is: { pickedAt: null } },
+        },
+        include: { user: { select: { name: true, email: true } } },
+      })
+      for (const am of ams) {
+        if (!am.user.email) continue
+        try {
+          await sendLunchReminderEmail({
+            to: am.user.email,
+            memberName: am.user.name ?? am.user.email,
+            eventAt: event.eventAt,
+            venue: event.venue,
+            changeDeadline: deadline,
+            pickUrl: `${process.env.NEXTAUTH_URL ?? ''}/applicant`,
+          })
+          sent++
+        } catch (e) {
+          console.error('[lunch-reminders] send failed for', am.user.email, e)
+        }
+      }
+      await prisma.lunchEvent.update({
+        where: { id: event.id },
+        data: { reminderSentAt: new Date() },
+      })
+    } catch (e) {
+      console.error('[lunch-reminders] event failed', event.id, e)
+    }
+  }
+  return NextResponse.json({ ok: true, sent, processedEvents: events.length })
+}