feat: Add Google Taxonomy integration and product editing enhancements

- Implemented Google Taxonomy loading via AJAX in main_view.php, allowing users to select categories for products.
- Enhanced product editing modal to include fields for product title, description, and Google category selection.
- Updated AJAX calls to save product data, including custom title, description, and selected Google category.
- Added character count validation for product title input.
- Integrated Select2 for improved category selection UI.
- Created google-taxonomy.php to fetch and cache Google Taxonomy data, ensuring efficient retrieval and fallback mechanisms.
- Removed outdated custom feed XML file.
- Updated layout-logged.php to include necessary Select2 styles and scripts.

layout/style.scss

@@ -1335,4 +1335,75 @@ table {
 .comment-form .hint {
   font-size: 12px;
   color: #666;
+}
+
+/* === Select2 w modalu "Edytuj produkt" === */
+
+/* pełna szerokość i taki sam odstęp jak inne pola */
+.jconfirm-box .form-group .select2-container {
+  width: 100% !important;
+  margin-top: 8px;
+}
+
+/* wygląd "inputa" */
+.jconfirm-box .select2-container--default .select2-selection--single {
+  background-color: #fff;
+  border: 1px solid #ced4da;
+  /* jak bootstrapowe inputy */
+  border-radius: 3px;
+  min-height: 42px;
+  /* wysokość podobna do pola tytułu/opisu */
+  display: flex;
+  align-items: center;
+  padding: 4px 12px;
+  box-shadow: none;
+  transition: border-color .15s ease-in-out, box-shadow .15s ease-in-out;
+  font-size: 14px;
+}
+
+/* tekst w środku */
+.jconfirm-box .select2-container--default .select2-selection--single .select2-selection__rendered {
+  padding-left: 0;
+  line-height: 1.4;
+  color: #495057;
+}
+
+/* placeholder */
+.jconfirm-box .select2-container--default .select2-selection--single .select2-selection__placeholder {
+  color: #adb5bd;
+}
+
+/* strzałka po prawej – wyrównanie */
+.jconfirm-box .select2-container--default .select2-selection--single .select2-selection__arrow {
+  height: 100%;
+  right: 8px;
+}
+
+/* efekt hover/focus – jak na form-control */
+.jconfirm-box .select2-container--default.select2-container--focus .select2-selection--single,
+.jconfirm-box .select2-container--default .select2-selection--single:hover {
+  border-color: #80bdff;
+  box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, .25);
+  outline: 0;
+}
+
+/* dropdown (lista kategorii) */
+.jconfirm-box .select2-container .select2-dropdown {
+  border-color: #ced4da;
+  border-radius: 0 0 3px 3px;
+  font-size: 14px;
+}
+
+/* pole wyszukiwania w dropdownie */
+.jconfirm-box .select2-container .select2-search--dropdown .select2-search__field {
+  padding: 6px 10px;
+  border-radius: 3px;
+  border: 1px solid #ced4da;
+  font-size: 14px;
+}
+
+/* podświetlenie zaznaczonej pozycji */
+.jconfirm-box .select2-container--default .select2-results__option--highlighted[aria-selected] {
+  background-color: #007bff;
+  color: #fff;
 }