Fix 10 known bugs: catalog, single product, and account pages (v0.1.5)

Catalog: page title via woocommerce_page_title(), breadcrumbs, category
template rename (underscore), 3-column grid, single chevron on sort.

Single product: variable form data attributes + disabled CSS class fix
(WC JS only toggles CSS classes, not HTML disabled attribute), dark mode
select specificity (0,5,1) to beat WC's (0,4,3) background shorthand,
gallery main image in thumbnail strip with empty URL guard, related/
upsells setup_postdata for correct global $product, grouped product
loop logic rewrite.

Account: downloads via wc_get_customer_available_downloads().

New: product-gallery.js, sanitize_title filter, wc_setup_product_data()
and wp_reset_postdata() Twig functions, product-thumbnails.html.twig
suppressor. Removed obsolete PLAN.md and SETUP.md.

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

CHANGELOG.md

@@ -2,6 +2,35 @@
 
 All notable changes to this project will be documented in this file.
 
+## [0.1.5] - 2026-03-01
+
+### Fixed
+
+- **Empty page title on catalog pages** (`header.html.twig`): Replaced `page_title` context variable (never passed by WC) with direct `fn('woocommerce_page_title', false)` call
+- **Missing breadcrumbs on catalog pages** (`archive-product.php`): Added `woocommerce_breadcrumb()` call before shop loop header
+- **Missing product categories on catalog pages** (`content-product-cat.html.twig`): Renamed template from hyphen (`content-product-cat`) to underscore (`content-product_cat`) to match WC's `wc_get_template()` filename convention
+- **Product grid 4 columns instead of 3** (`functions.php`, `loop-start.html.twig`): Changed default columns from 4 to 3 for better card proportions with sidebar
+- **Double chevron on sort dropdown** (`wc-bootstrap.css`): Removed conflicting `appearance: auto` rule; set `appearance: none` to let Bootstrap's `form-select` class handle the dropdown arrow exclusively
+- **Variable product add-to-cart button stays disabled** (`variable.html.twig`, `variation-add-to-cart-button.html.twig`): Added missing `data-product_id` and `data-product_variations` attributes to form; replaced HTML `disabled` attribute on button with CSS classes `disabled wc-variation-selection-needed` (WC JS only toggles CSS classes, never removes the HTML attribute)
+- **Variable product select white background in dark mode** (`wc-bootstrap.css`): Increased dark mode override specificity to `(0,5,1)` to beat WC's `.woocommerce div.product form.cart .variations select` at `(0,4,3)` which uses `background` shorthand; also overrides `background-image` for Bootstrap's dark-mode-aware chevron SVG
+- **Product gallery missing main image in thumbnail strip** (`product-image.html.twig`): Prepend main image ID to gallery IDs using `[post_thumbnail_id]|merge(gallery_image_ids)` with active state on first thumbnail; added `{% if thumb_url %}` guard to skip invalid attachment IDs
+- **Related/upsells products show same product repeated** (`related.html.twig`, `up-sells.html.twig`): Added `wc_setup_product_data()` call before each product render and `wp_reset_postdata()` after loop to set global `$product` correctly for WC hooks
+- **Grouped product add-to-cart button/pricing broken** (`grouped.html.twig`): Rewrote template to compute `quantites_required` and `show_add_to_cart_button` in loop (matching WC PHP logic); moved hidden `add-to-cart` input outside conditional; added `has_options()` and `is_sold_individually()` checks
+- **Downloads page empty** (`downloads.html.twig`): Replaced fragile `fn('WC').customer.get_downloadable_products()` chain with direct `fn('wc_get_customer_available_downloads', get_current_user_id())` call
+
+### Added
+
+- **Product gallery JS** (`product-gallery.js`): Vanilla JS click handler for thumbnail-to-main-image swap with active state highlighting and gallery fade-in
+- **`wc_setup_product_data()` Twig function** (`WooCommerceExtension.php`): Sets `$GLOBALS['product']` and calls `setup_postdata()` for correct product context in Twig loops
+- **`wp_reset_postdata` Twig function** (`WooCommerceExtension.php`): Restores global post state after product loops
+- **`sanitize_title` Twig filter** (`WooCommerceExtension.php`): Matches WC PHP's lowercase attribute name handling for variation form data attributes
+- **Product thumbnails suppressor** (`product-thumbnails.html.twig`): Empty template override to prevent WC's default full-size gallery images rendering below custom thumbnail row
+
+### Changed
+
+- **Whitelisted functions** (`WooCommerceExtension.php`): Added `woocommerce_page_title` and `wc_get_customer_available_downloads` to `ALLOWED_FUNCTIONS`
+- **Removed obsolete files**: Deleted `PLAN.md` and `SETUP.md` (superseded by CLAUDE.md)
+
 ## [0.1.4] - 2026-03-01
 
 ### Security