Implement Phase 2: product archive and shop loop templates (Bootstrap 5)

Add 15 Twig template overrides for the product archive and shop loop:
- archive-product: 3+9 grid layout with optional filter sidebar
- content-product: card component with hook-based content injection
- content-product-cat: category card with thumbnail
- product-searchform: input-group with search icon button
- loop/loop-start, loop-end: responsive row-cols grid
- loop/header: archive title with description hook
- loop/result-count: showing X-Y of Z with aria-relevant
- loop/orderby: form-select-sm sort dropdown
- loop/pagination: delegates to components/pagination.html.twig
- loop/no-products-found: alert-info empty state
- loop/add-to-cart: btn-primary-sm with AJAX data attributes
- loop/price: fw-semibold with sale/regular markup
- loop/rating: Bootstrap Icon stars (full, half, empty)
- loop/sale-flash: badge bg-danger positioned overlay

CSS additions: product card hover, sale badge z-index, star rating sizing,
price del/ins styling, WooCommerce grid reset.

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

templates/loop/result-count.html.twig

@@ -0,0 +1,33 @@
+{#
+ # Result Count (Bootstrap 5 Override)
+ #
+ # Displays the "Showing X-Y of Z results" text.
+ #
+ # Expected context:
+ #   total    - Total number of products
+ #   per_page - Products per page
+ #   current  - Current page number
+ #   orderedby - Whether results are currently sorted (optional)
+ #
+ # WooCommerce PHP equivalent: loop/result-count.php
+ #
+ # @package WcBootstrap
+ # @since 0.1.0
+ #}
+
+<p class="woocommerce-result-count text-body-secondary mb-0"
+   role="alert"
+   aria-relevant="all"
+   {% if orderedby is defined and orderedby %}data-is-sorted-by="true"{% endif %}>
+    {% if total is defined %}
+        {% set first = ((current|default(1) - 1) * per_page|default(total)) + 1 %}
+        {% set last = current|default(1) * per_page|default(total) %}
+        {% if last > total %}{% set last = total %}{% endif %}
+
+        {% 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) }}
+        {% endif %}
+    {% endif %}
+</p>