fix(admin): dedup pending maintenance notifications (updated_at claim + staleness threshold)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/Livewire/Admin/Maintenance.php

@@ -20,6 +20,9 @@ use Livewire\Component;
 #[Layout('layouts.admin')]
 class Maintenance extends Component
 {
+    /** A pending notification is presumed failed (retryable) after this long. */
+    private const RETRY_AFTER_MIN = 60;
+
     #[Validate('required|string|max:255')]
     public string $title = '';
 
@@ -188,11 +191,20 @@ class Maintenance extends Component
             ['maintenance_window_id' => $window->id, 'customer_id' => $customer->id, 'event' => $event],
             ['email' => $customer->email],
         );
-        // Delivered rows (sent_at set by the MessageSent listener) are final; a
-        // row that is still unconfirmed (sent_at null) is retryable — re-queue it.
+
+        // Delivered rows (sent_at set by the MessageSent listener) are final.
         if ($delivery->sent_at !== null) {
             return;
         }
+        // Otherwise the row is pending. Re-queue only when this is a fresh claim
+        // or the previous attempt is stale enough to be presumed failed — so a
+        // resend while the job is still in flight does not duplicate the email.
+        // updated_at is the last-attempt marker (touched on every dispatch).
+        if (! $delivery->wasRecentlyCreated && $delivery->updated_at->gt(now()->subMinutes(self::RETRY_AFTER_MIN))) {
+            return;
+        }
+
+        $delivery->forceFill(['updated_at' => now()])->save();
         $mail->notificationId = $delivery->id;
         Mail::to($customer->email)
             ->locale($customer->locale ?: config('app.locale'))

tests/Feature/Admin/MaintenanceTest.php

@@ -42,6 +42,10 @@ it('publishes a window and emails affected customers once (idempotent)', functio
     expect(fn () => MaintenanceNotification::query()->create([
         'maintenance_window_id' => $window->id, 'customer_id' => $customer->id, 'event' => 'announcement', 'email' => $customer->email,
     ]))->toThrow(Illuminate\Database\UniqueConstraintViolationException::class);
+
+    // Resending while the first mail is still pending must NOT duplicate.
+    Livewire::actingAs(operator('Owner'))->test(Maintenance::class)->call('resend', $window->uuid);
+    Mail::assertQueued(MaintenanceAnnouncementMail::class, 1);
 });
 
 it('emails a cancellation to customers who were announced', function () {