Fix add-to-cart button alignment in product cards (v0.1.10)

Add mt-auto to card-footer so the button is always pinned to the
bottom of the card, even when the product has no price.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -345,10 +345,19 @@ The child theme inherits from `wp-bootstrap` via WordPress `Template: wp-bootstr
 
 ## Version History
 
-Current version: **v0.1.9**
+Current version: **v0.1.10**
 
 ## Session History
 
+### 2026-03-29 — v0.1.10 Fix Add-to-Cart Button Alignment
+
+**Scope:** Fixed product card button jumping when price is missing (e.g., composable products).
+
+**Files modified (2):**
+
+- `templates/content-product.html.twig` — Added `mt-auto` to card-footer to pin button to card bottom
+- `style.css` — Version bump 0.1.9 → 0.1.10
+
 ### 2026-03-29 — v0.1.9 Category Tree Full-Width Items
 
 **Scope:** Made category tree items span the full parent/offcanvas width.