Release version 1.2.6 - Critical bugfixes for v1.2.5 features

Fixed two critical issues that prevented v1.2.5 features from working:

1. Parent Product Pricing Forms Not Visible (Critical)
   - Variable products were missing admin UI for parent pricing configuration
   - v1.2.5 implemented backend logic but forgot the admin forms
   - Added add_variable_parent_pricing_fields() method
   - Modified existing methods to skip variable products (simple only)
   - Parent pricing now fully functional with matching UI

2. Table Headers Not Hiding When Empty
   - CSS sibling selector ~ doesn't work when thead comes before tbody
   - Removed incorrect selector, kept only :has() pseudo-class
   - Added !important flag for proper specificity
   - Modern browser support (Chrome 105+, Firefox 121+, Safari 15.4+)

Changed files:
- includes/class-wc-tpp-product-meta.php - Added parent pricing forms
- assets/css/admin.css - Fixed header hiding CSS
- wc-tier-and-package-prices.php - Version 1.2.6
- composer.json - Version 1.2.6
- CHANGELOG.md - Detailed release notes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

wc-tier-and-package-prices.php

@@ -4,7 +4,7 @@
  * Plugin Name: WooCommerce Tier and Package Prices
  * Plugin URI: https://src.bundespruefstelle.ch/magdev/wc-tier-package-prices
  * Description: Add tier pricing and package prices to WooCommerce products with configurable quantities at fixed prices
- * Version: 1.2.5
+ * Version: 1.2.6
  * Author: Marco Graetsch
  * Author URI: https://src.bundespruefstelle.ch/magdev
  * Text Domain: wc-tier-package-prices
@@ -23,7 +23,7 @@ if (!defined('ABSPATH')) {
 
 // Define plugin constants
 if (!defined('WC_TPP_VERSION')) {
-    define('WC_TPP_VERSION', '1.2.5');
+    define('WC_TPP_VERSION', '1.2.6');
 }
 if (!defined('WC_TPP_PLUGIN_DIR')) {
     define('WC_TPP_PLUGIN_DIR', plugin_dir_path(__FILE__));