Wallet-Topup ueber Stripe (Credit-Pakete mit Bonus-Staffel)

End-to-end-Aufladung der Credit-Wallet, spiegelt den Einzel-PM-Fluss:

- Paket-Staffel mit Bonus in config/credits.php (10->10, 25->27, 50->55,
  100->115 Credits; price_cents netto, Stripe Tax ergaenzt USt.)
- credit_topups (Pending->Paid) + CreditTopupService: startTopup legt den
  Pending-Kauf an, fulfill() schreibt die Wallet idempotent gut (credited_at)
- StripeCheckoutService::forCreditTopup via checkoutCharge + credit_topup_id
  Metadata; ProcessStripeWebhook schreibt bei checkout.session.completed gut
- Checkout-Route /admin/me/checkout/credits/{pack} mit Rechnungsadress-Gate

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

app/Models/CreditTopup.php

@@ -0,0 +1,44 @@
+<?php
+
+namespace App\Models;
+
+use App\Enums\SinglePurchaseStatus;
+use App\Services\Billing\CreditTopupService;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+/**
+ * Eine Wallet-Aufladung über Stripe. Anlage/Erfüllung über
+ * {@see CreditTopupService}.
+ */
+class CreditTopup extends Model
+{
+    protected $fillable = [
+        'user_id',
+        'pack_key',
+        'credits',
+        'price_cents',
+        'currency',
+        'status',
+        'stripe_checkout_session_id',
+        'stripe_payment_intent_id',
+        'paid_at',
+        'credited_at',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'credits' => 'integer',
+            'price_cents' => 'integer',
+            'status' => SinglePurchaseStatus::class,
+            'paid_at' => 'datetime',
+            'credited_at' => 'datetime',
+        ];
+    }
+
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+}

app/Models/User.php

@@ -316,6 +316,11 @@ class User extends Authenticatable implements MustVerifyEmail
         return $this->hasMany(ReviewCheck::class);
     }
 
+    public function creditTopups(): HasMany
+    {
+        return $this->hasMany(CreditTopup::class);
+    }
+
     /**
      * Aktuelles Credit-Guthaben (1 Credit = 1 €). 0, solange keine Wallet
      * angelegt wurde.