fix(marketplace): fix product date format and improve UX

- Convert expires_at to ISO 8601 format for backend compatibility
- Update local state instead of reloading list on edit/create/delete
- Improve delete error message for products with related orders

marketplace/src/pages/admin/ProductsPage.tsx

@@ -51,21 +51,35 @@ export function ProductsPage() {
     const handleSubmit = async (e: React.FormEvent) => {
         e.preventDefault()
         try {
+            // Convert date to ISO 8601 format for backend
+            const expiresAtISO = formData.expires_at
+                ? new Date(formData.expires_at + 'T00:00:00Z').toISOString()
+                : undefined
+
             if (editingProduct) {
-                await adminService.updateProduct(editingProduct.id, {
+                const updated = await adminService.updateProduct(editingProduct.id, {
                     name: formData.name,
                     description: formData.description,
                     batch: formData.batch,
-                    expires_at: formData.expires_at,
+                    expires_at: expiresAtISO,
                     price_cents: formData.price_cents,
                     stock: formData.stock
                 })
+                // Update local state instead of reloading
+                setProducts(prev => prev.map(p =>
+                    p.id === editingProduct.id ? { ...p, ...updated } : p
+                ))
             } else {
-                await adminService.createProduct(formData)
+                const newProduct = await adminService.createProduct({
+                    ...formData,
+                    expires_at: expiresAtISO || ''
+                })
+                // Add to local state
+                setProducts(prev => [newProduct, ...prev])
+                setTotal(prev => prev + 1)
             }
             setShowModal(false)
             resetForm()
-            loadProducts()
         } catch (err) {
             console.error('Error saving product:', err)
             alert('Erro ao salvar produto')
@@ -76,10 +90,18 @@ export function ProductsPage() {
         if (!confirm('Tem certeza que deseja excluir este produto?')) return
         try {
             await adminService.deleteProduct(id)
-            loadProducts()
-        } catch (err) {
+            // Update local state instead of reloading
+            setProducts(prev => prev.filter(p => p.id !== id))
+            setTotal(prev => prev - 1)
+        } catch (err: unknown) {
             console.error('Error deleting product:', err)
-            alert('Erro ao excluir produto')
+            // Check if it's a constraint error (product has orders)
+            const message = (err as { response?: { data?: { error?: string } } })?.response?.data?.error
+            if (message?.includes('related orders')) {
+                alert('Não é possível excluir: este produto possui pedidos relacionados.')
+            } else {
+                alert('Erro ao excluir produto')
+            }
         }
     }