chore: remove WooCommerce from theme — not used on peptiderepo.com (v1.7.0)

Remove all WC asset dequeue logic, cart icon conditional, and WC-specific tests from the theme. Eliminates the class of fatal errors seen in the 2026-04-23 incident where is_woocommerce() was called after WC deactivation.

Version: 1.6.x → 1.7.0
Reviewed-by: peptiderepo (CTO)
QA: qa-reviews/peptide-starter-theme/2026-04-23-d239bd1e.md

CONVENTIONS.md

@@ -460,11 +460,6 @@ if ( is_active_sidebar( 'footer-1' ) ) {
 
 ### Class Existence Check
 
-**For WooCommerce:**
-```php
-if ( class_exists( 'WooCommerce' ) ) {
-  // Render cart icon
-}
 ```
 
 **For post types:**