Add Bootstrap 5 single product page layout

Add two-column responsive grid (image gallery + product summary) for
single product pages, following the same bridge pattern used for
product archives.

Key changes:
- Create content-single-product.php bridge and Twig layout template
- Add single product renderer at template_redirect priority 11
- Disable WooCommerce block compatibility layer that strips classic
  hooks when parent theme has theme.json
- Move PHP templates to woocommerce/ subfolder for cleaner structure
- Fix Twig templates to self-compute context data not passed by
  wc_get_template() (tabs, short-description, meta, rating)
- Fix Underscore.js triple-brace syntax conflict in variation template
  by wrapping in {% verbatim %}

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

templates/single-product/add-to-cart/variation.html.twig

@@ -11,6 +11,7 @@
  # @since 0.1.0
  #}
 
+{% verbatim %}
 <script type="text/template" id="tmpl-variation-template">
     <div class="woocommerce-variation-description mb-2">
         {{{ data.variation.variation_description }}}
@@ -22,6 +23,7 @@
         {{{ data.variation.availability_html }}}
     </div>
 </script>
+{% endverbatim %}
 
 <script type="text/template" id="tmpl-unavailable-variation-template">
     <p class="alert alert-warning mb-0">

templates/single-product/meta.html.twig

@@ -4,12 +4,7 @@
  # Renders SKU, categories, and tags as a definition list.
  #
  # Expected context:
- #   product - WC_Product object with:
- #     .get_sku()          - SKU string
- #     .get_id()           - Product ID
- #   sku                   - SKU string (fallback)
- #   categories_html       - Pre-rendered category links HTML
- #   tags_html             - Pre-rendered tag links HTML
+ #   product - WC_Product object (from TemplateOverride)
  #
  # WooCommerce PHP equivalent: single-product/meta.php
  #
@@ -17,6 +12,14 @@
  # @since 0.1.0
  #}
 
+{# Compute categories/tags HTML when not passed as context. #}
+{% if categories_html is not defined %}
+    {% set categories_html = fn('wc_get_product_category_list', product.get_id(), ', ') %}
+{% endif %}
+{% if tags_html is not defined %}
+    {% set tags_html = fn('wc_get_product_tag_list', product.get_id(), ', ') %}
+{% endif %}
+
 <div class="product_meta border-top pt-3 mt-3">
     {{ do_action('woocommerce_product_meta_start') }}
 
@@ -26,13 +29,13 @@
             <dd class="col-sm-9">{{ product.get_sku()|esc_html }}</dd>
         {% endif %}
 
-        {% if categories_html is defined and categories_html %}
-            <dt class="col-sm-3 text-body-secondary">{{ __('Categories:') }}</dt>
+        {% if categories_html %}
+            <dt class="col-sm-3 text-body-secondary">{{ fn('_n', 'Category:', 'Categories:', product.get_category_ids()|length, 'woocommerce') }}</dt>
             <dd class="col-sm-9">{{ categories_html|raw }}</dd>
         {% endif %}
 
-        {% if tags_html is defined and tags_html %}
-            <dt class="col-sm-3 text-body-secondary">{{ __('Tags:') }}</dt>
+        {% if tags_html %}
+            <dt class="col-sm-3 text-body-secondary">{{ fn('_n', 'Tag:', 'Tags:', product.get_tag_ids()|length, 'woocommerce') }}</dt>
             <dd class="col-sm-9">{{ tags_html|raw }}</dd>
         {% endif %}
     </dl>

templates/single-product/rating.html.twig

@@ -4,10 +4,7 @@
  # Renders the star rating with review count link on the single product page.
  #
  # Expected context:
- #   product       - WC_Product object
- #   rating_count  - Number of ratings
- #   review_count  - Number of reviews
- #   average       - Average rating (0-5)
+ #   product - WC_Product object (from TemplateOverride)
  #
  # WooCommerce PHP equivalent: single-product/rating.php
  #
@@ -15,7 +12,17 @@
  # @since 0.1.0
  #}
 
-{% if rating_count is defined and rating_count > 0 %}
+{# Guard: bail if ratings are disabled. #}
+{% if fn('wc_review_ratings_enabled') %}
+
+{# Compute rating data from product object when not passed as context. #}
+{% if rating_count is not defined %}
+    {% set rating_count = product.get_rating_count() %}
+    {% set review_count = product.get_review_count() %}
+    {% set average = product.get_average_rating() %}
+{% endif %}
+
+{% if rating_count > 0 %}
     <div class="woocommerce-product-rating d-flex align-items-center gap-2 mb-3">
         <div class="wc-star-rating d-flex align-items-center gap-1"
              role="img"
@@ -31,10 +38,12 @@
             {% endfor %}
         </div>
 
-        {% if review_count is defined and review_count > 0 %}
+        {% if review_count > 0 %}
             <a href="#reviews" class="woocommerce-review-link text-body-secondary text-decoration-none small" rel="nofollow">
-                {{ _n('%s customer review', '%s customer reviews', review_count)|format(review_count) }}
+                {{ fn('_n', '%s customer review', '%s customer reviews', review_count, 'woocommerce')|format(review_count) }}
             </a>
         {% endif %}
     </div>
 {% endif %}
+
+{% endif %}{# wc_review_ratings_enabled #}

templates/single-product/short-description.html.twig

@@ -2,7 +2,8 @@
  # Product Short Description (Bootstrap 5 Override)
  #
  # Expected context:
- #   short_description - Product short description HTML
+ #   product           - WC_Product object (from TemplateOverride)
+ #   short_description - Product short description HTML (optional)
  #
  # WooCommerce PHP equivalent: single-product/short-description.php
  #
@@ -10,7 +11,12 @@
  # @since 0.1.0
  #}
 
-{% if short_description is defined and short_description %}
+{# Compute short description when not passed as context. #}
+{% if short_description is not defined %}
+    {% set short_description = apply_filters('woocommerce_short_description', product.get_short_description()) %}
+{% endif %}
+
+{% if short_description %}
     <div class="woocommerce-product-details__short-description lead text-body-secondary mb-3">
         {{ short_description|raw }}
     </div>

templates/single-product/tabs/tabs.html.twig

@@ -16,7 +16,12 @@
  # @since 0.1.0
  #}
 
-{% if product_tabs is defined and product_tabs|length > 0 %}
+{# Compute tabs from filter when not passed as context (wc_get_template passes no args). #}
+{% if product_tabs is not defined %}
+    {% set product_tabs = apply_filters('woocommerce_product_tabs', {}) %}
+{% endif %}
+
+{% if product_tabs|length > 0 %}
     <div class="woocommerce-tabs wc-tabs-wrapper mt-5">
         {# Tab navigation #}
         <ul class="nav nav-tabs" id="productTabs" role="tablist">