Add Bootstrap 5 product archive with card grid and sidebar

Replace WooCommerce's default shop/category page rendering with a
Bootstrap 5 card grid layout featuring responsive columns, sale badges,
star ratings, and an offcanvas sidebar for filters on mobile.

Key implementation details:

- Bypass parent theme's TemplateController for product archives via
  wp_bootstrap_should_render_template filter, render at template_redirect
  priority 11 using the same page shell injection pattern as plugin pages

- Add archive-product.php (Bootstrap layout with optional sidebar) and
  content-product.php (PHP bridge for wc_get_template_part interception)

- Inject global $product into Twig context in TemplateOverride to fix
  empty price/add-to-cart/rating/sale-flash in loop sub-templates — Twig
  has isolated variable scopes and cannot access PHP globals directly

- Fix pagination URLs: use get_pagenum_link() instead of ?page= query
  param (WordPress uses 'paged' for archive pagination, not 'page')

- Fix double-escaped – in result count by adding |raw filter

- Reset WooCommerce float-based layout CSS (woocommerce-layout.css) for
  shop pages to prevent conflicts with Bootstrap flex grid

- Register shop-sidebar widget area with Bootstrap-styled markup

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

templates/loop/loop-start.html.twig

@@ -12,6 +12,6 @@
  # @since 0.1.0
  #}
 
-{% set cols = columns|default(3) %}
+{% set cols = columns|default(4) %}
 
-<div class="row row-cols-1 row-cols-sm-2 row-cols-md-{{ cols < 3 ? cols : 3 }} row-cols-lg-{{ cols }} g-4 products">
+<div class="row row-cols-1 row-cols-sm-2 row-cols-md-3 row-cols-lg-{{ cols }} g-4 products">

templates/loop/result-count.html.twig

@@ -27,7 +27,7 @@
         {% if total <= per_page|default(total) or total == 0 %}
             {{ _n('Showing the single result', 'Showing all %d results', total)|format(total) }}
         {% else %}
-            {{ __('Showing %1$d&ndash;%2$d of %3$d results')|format(first, last, total) }}
+            {{ __('Showing %1$d&ndash;%2$d of %3$d results')|format(first, last, total)|raw }}
         {% endif %}
     {% endif %}
 </p>