feat: add day-3 branded payment-failure reminder mailable

app/Mail/PaymentFailedDay3Reminder.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace App\Mail;
+
+use App\Models\User;
+use App\Services\PlanFeatures;
+use Illuminate\Mail\Mailable;
+use Illuminate\Mail\Mailables\Content;
+use Illuminate\Mail\Mailables\Envelope;
+
+final class PaymentFailedDay3Reminder extends Mailable
+{
+    public function __construct(public readonly User $user) {}
+
+    public function envelope(): Envelope
+    {
+        return new Envelope(
+            subject: 'Heads up — your FuelAlert payment is retrying',
+        );
+    }
+
+    public function content(): Content
+    {
+        return new Content(
+            markdown: 'emails.payment-failed-day-3',
+            with: [
+                'name' => $this->user->name,
+                'tier' => PlanFeatures::for($this->user)->tier(),
+                'portalUrl' => route('billing.portal'),
+            ],
+        );
+    }
+}