feat(admin): Weeztix setup wizard, integration status badges

- Summary view when Weeztix is configured; edits only via 3-step wizard
- Step 1: reuse or replace OAuth client ID/secret; callback URL shown
- Step 2: OAuth connect (resume wizard after callback when started from wizard)
- Step 3: coupon, prefix, usage; finishing exits wizard
- PreregistrationPage: mailwizz/weeztix integration status helpers
- Pages index: Integrations column with MW/WZ badges; edit page: status cards

Made-with: Cursor

app/Http/Controllers/Admin/PageController.php

@@ -28,7 +28,7 @@ class PageController extends Controller
     {
         $query = PreregistrationPage::query()
             ->withCount('subscribers')
-            ->with('weeztixConfig')
+            ->with(['weeztixConfig', 'mailwizzConfig'])
             ->orderByDesc('start_date');
 
         if (! $request->user()?->isSuperadmin()) {
@@ -86,7 +86,11 @@ class PageController extends Controller
 
     public function edit(PreregistrationPage $page): View
     {
-        $page->load(['blocks' => fn ($q) => $q->orderBy('sort_order')]);
+        $page->load([
+            'blocks' => fn ($q) => $q->orderBy('sort_order'),
+            'mailwizzConfig',
+            'weeztixConfig',
+        ]);
 
         return view('admin.pages.edit', compact('page'));
     }