feat: refine price formatting and enable dynamic color updates in cart

- Updated price slider and backend formatting to round values instead of showing decimals
- Enhanced product detail page with active color selection display and automatic cart updates
- Adjusted swatch behavior to dynamically update the selected color in the cart via AJAX
- Improved consistency in slider steps and price formatting throughout templates and views

templates/catalog/_fragments/side-bar.html

@@ -64,7 +64,7 @@
                         type="range"
                         min="{{ price_slider_min_bound }}"
                         max="{{ price_slider_max_bound }}"
-                        step="0.01"
+                        step="1"
                         value="{{ price_slider_selected_min }}"
                         class="catalog-price-slider__range"
                         aria-label="Минимальная цена"
@@ -74,7 +74,7 @@
                         type="range"
                         min="{{ price_slider_min_bound }}"
                         max="{{ price_slider_max_bound }}"
-                        step="0.01"
+                        step="1"
                         value="{{ price_slider_selected_max }}"
                         class="catalog-price-slider__range"
                         aria-label="Максимальная цена"