refactor(stock): centralize reservation aggregate

app/Domains/Purchase/Models/Purchase.php

@@ -19,6 +19,7 @@ use Illuminate\Support\Facades\DB;
 
 #[Fillable([
     'cart_id',
+    'stock_reservation_id',
     'tenant_codigo',
     'user_id',
     'status',
@@ -77,6 +78,7 @@ class Purchase extends Model
     {
         return [
             'cart_id' => 'integer',
+            'stock_reservation_id' => 'integer',
             'user_id' => 'integer',
             'expires_at' => 'datetime',
             'total' => 'decimal:2',
@@ -123,10 +125,10 @@ class Purchase extends Model
         return $this->hasMany(Ticket::class, 'source_purchase_id');
     }
 
-    /** @return HasMany<StockReservation, $this> */
-    public function stockReservations(): HasMany
+    /** @return BelongsTo<StockReservation, $this> */
+    public function stockReservation(): BelongsTo
     {
-        return $this->hasMany(StockReservation::class);
+        return $this->belongsTo(StockReservation::class);
     }
 
     /**