Release version 1.1.6 - Critical fix for plugin activation

Fixed critical bug that prevented plugin activation in v1.1.3, v1.1.4, and v1.1.5.

Root Cause:
- WC_TPP_Cart and WC_TPP_Frontend classes were instantiated immediately when
  their files were loaded (via `new ClassName();` at bottom of files)
- This happened BEFORE WooCommerce was fully loaded
- Hook registration attempted to access WooCommerce functions before they existed
- Result: Fatal error during plugin activation

Solution:
- Removed immediate instantiation from class-wc-tpp-cart.php (line 251)
- Removed immediate instantiation from class-wc-tpp-frontend.php (line 186)
- Added init_classes() method to main plugin class
- Classes now instantiated via woocommerce_loaded hook
- Ensures WooCommerce is fully initialized before any hooks are registered

Changes:
- includes/class-wc-tpp-cart.php - Removed `new WC_TPP_Cart();`
- includes/class-wc-tpp-frontend.php - Removed `new WC_TPP_Frontend();`
- wc-tier-and-package-prices.php - Added init_classes() and woocommerce_loaded hook
- CHANGELOG.md - Added v1.1.6 section
- composer.json - Version 1.1.6
- All translation files updated to 1.1.6
- All .mo files recompiled

This fix ensures proper WordPress plugin lifecycle:
1. Plugin file loaded
2. Classes defined (but not instantiated)
3. WooCommerce loads
4. woocommerce_loaded hook fires
5. Classes instantiated with full WooCommerce availability

🤖 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/wc-tier-package-prices
  * Description: Add tier pricing and package prices to WooCommerce products with configurable quantities at fixed prices
- * Version: 1.1.5
+ * Version: 1.1.6
  * Author: Marco Graetsch
  * Author URI: https://src.bundespruefstelle.ch/magdev
  * Text Domain: wc-tier-package-prices
@@ -22,7 +22,7 @@ if (!defined('ABSPATH')) {
 }
 
 // Define plugin constants
-define('WC_TPP_VERSION', '1.1.5');
+define('WC_TPP_VERSION', '1.1.6');
 define('WC_TPP_PLUGIN_DIR', plugin_dir_path(__FILE__));
 define('WC_TPP_PLUGIN_URL', plugin_dir_url(__FILE__));
 define('WC_TPP_PLUGIN_BASENAME', plugin_basename(__FILE__));
@@ -78,6 +78,14 @@ class WC_Tier_Package_Prices {
         require_once WC_TPP_PLUGIN_DIR . 'includes/class-wc-tpp-product-meta.php';
         require_once WC_TPP_PLUGIN_DIR . 'includes/class-wc-tpp-frontend.php';
         require_once WC_TPP_PLUGIN_DIR . 'includes/class-wc-tpp-cart.php';
+
+        // Instantiate classes after WooCommerce is loaded
+        add_action('woocommerce_loaded', array($this, 'init_classes'));
+    }
+
+    public function init_classes() {
+        new WC_TPP_Frontend();
+        new WC_TPP_Cart();
     }
 
     public function declare_hpos_compatibility() {