feat: initial project with Phase 1 complete

app/Http/Controllers/Admin/SubscriberController.php

@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Http\Controllers\Admin;
+
+use App\Http\Controllers\Controller;
+use App\Models\PreregistrationPage;
+
+class SubscriberController extends Controller
+{
+    public function index(PreregistrationPage $page): \Illuminate\View\View
+    {
+        return view('admin.subscribers.index', compact('page'));
+    }
+
+    public function export(PreregistrationPage $page): \Symfony\Component\HttpFoundation\StreamedResponse
+    {
+        $this->authorize('view', $page);
+
+        $subscribers = $page->subscribers()->orderBy('created_at')->get();
+
+        return response()->streamDownload(function () use ($subscribers, $page) {
+            $handle = fopen('php://output', 'w');
+            fputcsv($handle, ['First Name', 'Last Name', 'Email', 'Phone', 'Registered At']);
+            foreach ($subscribers as $sub) {
+                fputcsv($handle, [
+                    $sub->first_name,
+                    $sub->last_name,
+                    $sub->email,
+                    $sub->phone,
+                    $sub->created_at->toDateTimeString(),
+                ]);
+            }
+            fclose($handle);
+        }, "subscribers-{$page->slug}.csv");
+    }
+}