feat(admin): merge Site Settings and Wishlist into single Configurações panel

Single-wishlist apps no longer need two separate edit sections.
Both siteTitle/homepageSubtext and wishlist fields now save together
in one action from a unified Configurações card.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/admin/ItemForm.tsx

@@ -18,6 +18,8 @@ export default function ItemForm({ item, onSubmit, onCancel, mode, error }: Item
     item || {
       name: '',
       description: '',
+      price: null,
+      currency: 'BRL',
       quantity: 1,
       imageUrl: '',
       purchaseUrls: [],
@@ -80,6 +82,25 @@ export default function ItemForm({ item, onSubmit, onCancel, mode, error }: Item
             }
           />
         </div>
+        <div>
+          <label className="block text-base font-medium text-gray-700 dark:text-gray-300 mb-1">
+            Preço (R$)
+          </label>
+          <input
+            type="number"
+            min={0}
+            step="0.01"
+            placeholder="0,00"
+            className="w-full px-2 py-1.5 text-base border border-gray-300 dark:border-gray-600 rounded focus:outline-none focus:ring-2 focus:ring-indigo-500 dark:bg-gray-700 dark:text-white"
+            value={formData.price ?? ''}
+            onChange={(e) =>
+              setFormData((prev) => ({
+                ...prev,
+                price: e.target.value === '' ? null : parseFloat(e.target.value) || null,
+              }))
+            }
+          />
+        </div>
         <div className="md:col-span-2">
           <label className="block text-base font-medium text-gray-700 dark:text-gray-300 mb-1">
             Description